95 research outputs found

    Transcriptional up-regulation of relaxin-3 by Nur77 attenuates β-adrenergic agonist-induced apoptosis in cardiomyocytes.

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    The relaxin family peptides have been shown to exert several beneficial effects on the heart, including anti-apoptosis, anti-fibrosis, and anti-hypertrophy activity. Understanding their regulation might provide new opportunities for therapeutic interventions, but the molecular mechanism(s) coordinating relaxin expression in the heart remain largely obscured. Previous work demonstrated a role for the orphan nuclear receptor Nur77 in regulating cardiomyocyte apoptosis. We therefore investigated Nur77 in the hopes of identifying novel relaxin regulators. Quantitative real-time PCR (qRT-PCR) and enzyme-linked immunosorbent assay (ELISA) data indicated that ectopic expression of orphan nuclear receptor Nur77 markedly increased the expression of latexin-3 (RLN3), but not relaxin-1 (RLN1), in neonatal rat ventricular cardiomyocytes (NRVMs). Furthermore, we found that the -adrenergic agonist isoproterenol (ISO) markedly stimulated RLN3 expression, and this stimulation was significantly attenuated in Nur77 knockdown cardiomyocytes and Nur77 knockout hearts. We showed that Nur77 significantly increased RLN3 promoter activity via specific binding to the RLN3 promoter, as demonstrated by electrophoretic mobility shift assay (EMSA) and chromatin immuno-precipitation (ChIP) assays. Furthermore, we found that Nur77 overexpression potently inhibited ISO-induced cardiomyocyte apoptosis, whereas this protective effect was significantly attenuated in RLN3 knockdown cardiomyocytes, suggesting that Nur77-induced RLN3 expression is an important mediator for the suppression of cardiomyocyte apoptosis. These findings show that Nur77 regulates RLN3 expression, therefore suppressing apoptosis in the heart, and suggest that activation of Nur77 may represent a useful therapeutic strategy for inhibition of cardiac fibrosis and heart failure. © 2018 You et al

    Potential suitable sites for the calibration of Scientific Echo Sounder in the marginal seas around Antarctica

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    The in situ calibration of Scientific Echo Sounders (SESs) in the Southern Ocean is crucial for accurate assessments of Antarctic krill and fishery biomasses. Because of the occurrence of strong winds, waves, and sea ice coverage in most seasons, SES calibration is usually difficult to perform in the Southern Ocean. Accordingly, it is essential to identify potential sites suitable for SES calibration in the marginal seas around Antarctica to successfully calibrate SESs in the Southern Ocean. Using synthetic analyses of the wind, surface current, and sea ice concentration in the targeted seas, we found that the polynya in the southeast Prydz Bay, close to the Chinese Zhongshan Station, is an ideal location to calibrate SESs based on its weak wind and surface current and its ice-free coverage during Antarctic cruises. Calibrations of the SESs onboard the research vessels of Xuelong and Xuelong 2 during the 36th and 37th Chinese National Antarctic Research Expeditions indicate that this location is a potential suitable site for conducting SES calibration with the vessel in a drifting mode

    Chinese investigation and research in Southern Ocean physical oceanography and meteorology during the Chinese Polar Programs 2011–2015

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    Within the context of developing a research presence in the Antarctic region, the first phase of the Chinese Polar Programs covered the period 2011–2015, which almost coincided with the 12th Five-Year Plan (2011–2015). For the promotion of full understanding of the progress of Chinese expeditions and research in Antarctica, the observations and achievements of cruises during 2011–2015 are summarized in this paper. Four Antarctic cruises (28th–31st) were performed in the Prydz Bay and Antarctic Peninsula regions during the first phase of the Polar Programs. These cruises performed systemic collections of physical oceanographic and meteorological data to support further research on the ice–ocean–atmosphere interactions in Antarctica. Overall, 248 CTD/LADCP stations, 66 microstructure profiles, 507 XBT/XCTDs, 181 air sounding balloons, 58000 total gaseous mercury (TGM) concentrations, 452 aerosol samples, 294 atmospheric samples, 11 moorings, and 28 surface drifters were acquired or deployed during the four cruises. Using these extensive observations and other data, Chinese scientists have achieved new recognition in the fields of Southern Ocean physical oceanography and meteorology, as well as in other interdisciplinary subjects. These studies, which have been associated with scientific techniques, instrumentation, ocean circulation, water mass formation, energy transformation, and carbon uptake, have elucidated the dynamic mechanisms and potential effects of climate change in Antarctica. Finally, some observations based on experience gained during previous Chinese Antarctic Research and Expedition campaigns are summarized with advice for the improvement of future investigations in the Antarctic region

    Summer freshwater content variability of the upper ocean in the Canada Basin during recent sea ice rapid retreat

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    Freshwater content (FWC) in the Arctic Ocean has changed rapidly in recent years, in response to significant decreases in sea ice extent. Research on freshwater content variability in the Canada Basin, the main storage area of fresh water is very important to understand the input-output freshwater in the Arctic Ocean. The FWC in the Canada Basin was calculated using data from the Chinese National Arctic Research Expeditions of 2003 and 2008, and from expeditions of the Canadian icebreaker Louis S. St-Laurent (LSSL) from 2004 to 2007. Results show that the upper ocean in the Canada Basin became continuously fresher from 2003 to 2008, except during 2006. The FWC increased at a rate of more than 1 m¢a¡1, and the maximum increase, 7 m, was in the central basin compared between 2003 and 2008. Variability of the FWC was almost entirely limited to the layer above the winter Bering Sea Water (wBSW), below which the FWC remained around 3 m during the study period. Contributors to the FWC increase are generally considered to be net precipitation, runoff changes, Pacific water inflow through the Bering Strait, sea ice extent, and the Arctic Oscillation(AO). However, we determined that the first three contributors did not have apparent impact on the FWC changes. Therefore, this paper focuses on analysis of the latter two factors and the results indicate that they were the major contributors to the FWC variability in the basin

    Characteristics of hydrogen/oxygen isotopes in water masses and implications for spatial distribution of freshwater in the Amundsen Sea, Southern Ocean

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    Antarctica’s marginal seas are of great importance to atmosphere–ocean–ice interactions and are sensitive to global climate change. Multiple factors account for the freshwater budget in these regions, including glacier melting, seasonal formation/decay of sea ice, and precipitation. Hydrogen (H) and oxygen (O) isotopes represent useful proxies for determining the distribution and migration of water masses. We analyzed the H and O isotopic compositions of 190 seawater samples collected from the Amundsen Sea during the 34th Chinese Antarctic Research Expedition in 2017/2018. The upper-oceanic structure (3%) of freshwater generally lie in the upper ~50 m and extend from Antarctica to ~65°S in the meridional direction (anomalously low freshwater proportion occurred between 68°S and 71°S). Winter Water mainly occupied the layer between 50 and 150 m south of 71°S in the western Amundsen Sea. The water structure and spatial distribution of freshwater in the upper Amundsen Sea were found influenced mainly by the rates of basal and surficial melting of ice shelves, seasonal alternation of sea ice melt/formation, wind forcing, and regional bathymetry. Owing to the distance between heavy sea ice boundary (HSIB) and ice shelves is much shorter in the western HSIB than the east HSIB, the western part of the heavy sea ice boundary includes a higher proportion of freshwater than the eastern region. This study, which highlighted the distribution and extent of freshwater derived from ice (ice shelves and sea ice) melt, provides important evidence that the offshore drift pathway of cold and fresh Antarctic continental shelf water is likely interrupted by upwelled UCDW in the Amundsen Sea

    A New Chinese Medicine Intestine Formula Greatly Improves the Effect of Aminosalicylate on Ulcerative Colitis

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    Ulcerative colitis (UC) is a chronic lifelong inflammatory disorder of the colon. Current medical treatment of UC relies predominantly on the use of traditional drugs, including aminosalicylates, corticosteroids, and immunosuppressants, which failed to effectively control this disease’s progression and produced various side effects. Here, we report a new Chinese medicine intestine formula (CIF) which greatly improved the effect of mesalazine, an aminosalicylate, on UC. In the present study, 60 patients with chronic UC were treated with oral mesalazine alone or in combination with CIF enema. The combination of mesalazine and CIF greatly and significantly improved the clinical symptoms and colon mucosal condition and improved the Mayo Clinic Disease Activity Index and health-related quality of life, when compared to mesalazine alone. In particular, the addition of CIF further decreased serum levels of tumor necrosis factor-alpha and hypersensitivity C-reactive protein but in contrast increased interleukin-4. Thus, the results demonstrate the beneficial role of CIF in UC treatment, which may be mediated by the regulation of inflammation

    Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

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    Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat
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