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Introduction: Hypertension can accelerate and aggravate the process of arterial ageing and calcification. However, the mechanism behind has yet to be well elucidated. Methods: Here, we monitored the dynamic changes of fibronectin (FN)/α5 integrin, bone morphogenetic protein 2/matrix Gla protein (BMP2/MGP), and Runx2 in the aorta of spontaneously hypertensive rats (SHRs) and thoracic aortic vascular smooth muscle cells (VSMCs), also the phenotypic transformation of VSMCs during the process of arterial ageing and calcification. Further, study on arterial ageing and calcification through antagonist experiments at the molecular level was explored. Results: We found extracellular FN and its α5 integrin receptor expressions were positively associated with arterial ageing and calcification in SHR during ageing, as well in VSMCs from SHR in vitro. Integrin receptor inhibitor of GRGDSP would delay this arterial ageing and calcification process. Moreover, the elevated FN and α5 integrin receptor expression evoked the disequilibrium of BMP2/MGP, where the expression of BMP2, a potent osteogenic inducer, increased while MGP, a calcification inhibitor, decreased. Furthermore, it was followed by the upregulation of Runx2 and the phenotypic transformation of VSMCs from the contractile phenotype into the osteoblast-like cells. Notably, BMP2 antagonist of rmNoggin was sufficient to ameliorate the ageing and calcification process of VSMCs and exogenous BMP2-adding accelerate and aggregate the process. Conclusion: Our study revealed that hypertension-associated arterial ageing and calcification might be a consequence that hypertension up-regulated FN and its high binding affinity integrin α5 receptor in the aortic wall, which in turn aggravated the imbalance of BMP2/MGP, promoted the transcription of Runx2, and induced the phenotypic transformation of VSMCs from the contractile phenotype into the osteoblast-like cells. Our study would provide insights into hypertension-associated arterial ageing and calcification and shed new light on the control of arterial calcification, especially for those with hypertension. [ABSTRACT FROM AUTHOR]

Introduction: Pharmacological preconditioning limits myocardial infarct size after ischemia/reperfusion. Dexmedetomidine is an α2-adrenergic receptor agonist used in anesthesia that may have cardioprotective properties against ischemia/reperfusion injury. We investigated whether dexmedetomidine induces cardioprotection against myocardial apoptosis injury.Methods: In order to assess the role of dexmedetomidine on myocardial apoptosis, we established a grave scalding rat model. Blood and myocardial tissue from the ventriculus sinister were harvested, then troponin, myocardial apoptosis, and expression of caspase-12, GRP78, and CHOP were assessed.Results: Dexmedetomidine significantly reduced myocardial apoptosis, improved functional recovery, and reversed myocardial injury induced by grave scalding. The heart rate in the five groups studied was significantly different (p < 0.05). The number of buffy-stained nucleoli in the myocardial cell was highest in the simple scald group. The expression of caspase-12 obviously increased in the simple scald group. The expression of GRP78 and CHOP increased in the simple scald and scald and 50 μg/kg dexmedetomidine groups (p < 0.05).Conclusions: The results show that dexmedetomidine (DEX) produces cardioprotection against myocardial apoptosis injury. DEX is not only a useful sedative, but also plays a pivotal role in anesthetic cardioprotection. The potential benefits of DEX protection in high risk cardiovascular patients undergoing surgery are enormous. [ABSTRACT FROM AUTHOR]

Symbiotic integration of agricultural activities is widespread but quantitative assessments of the environmental benefits are scarce. To explore the potential benefits of applying the industrial symbiosis approach in agriculture and horticulture, a detailed case study is reported of a potential Eco-Industrial Park (EIP) including three activities: dairy farming, greenhouse cultivation of vegetables, and mushroom growing. These activities are widespread world-wide but, to enable quantitative assessment, the specific EIP studied is located in the Canadian province of British Columbia (BC). The activities are linked by anaerobic digestion of dairy manure to produce biogas and digestate. Biogas replaces natural gas to supply heat to the farms and carbon dioxide (CO 2) to the greenhouse. Digestate is separated into a liquid fertilizer and a solid substrate; the former replaces chemical fertilizers and the latter can be utilized as cow bedding and growing medium for plants and mushrooms. Mushroom growing emits CO 2 which is conventionally ventilated but can be used for stimulating plant growth in the greenhouse. Life Cycle Assessment (LCA) is used to quantify the environmental benefits of the EIP compared to conventional independent farms. Non-renewable energy consumption, greenhouse gas emissions, aquatic acidification, respiratory effects from organic emissions, and human toxicity can be reduced by 50%–90% and aquatic eutrophication and respiratory effects from inorganic emissions can be reduced by more than 10%. Such EIPs can also alleviate nutrient management problems in regions with intensive livestock farming. • An LCA model of EIP linking AD of dairy manure, greenhouse and mushroom operations. • Exchange of by-products enhances energy and material self-sufficiency. • Digestate utilisation within the EIP improves nutrient management. • Reductions of ∼60% achievable in non-renewable energy use and global warming potential. • Reductions of 10%–90% achievable across five other life cycle impact categories. [ABSTRACT FROM AUTHOR]

Liquefied natural gas (LNG) is a promising alternative to coal to mitigate the greenhouse gas (GHG) and particulate emissions from power, industry, and district heating in China. While numerous existing life cycle assessment (LCA) studies estimate the GHG footprint of LNG, large variation exists in these results. Such variability could be caused by differing project designs, system boundaries, modeling methods and data sources. It is not clear which of these factors is the most important. Here, three research groups from Canada and the US performed independent LCAs of the same planned LNG supply chain from Canada to China. The teams applied different methods and assumptions but used aligned system boundaries and worked with a single upstream producer to obtain production data. The GHG emissions of Canadian LNG to China for power and heat generation were found to be 427–556 g CO 2 -eq/kWh and 81–92 g CO 2 -eq/MJ. Compared with Chinese coal for power generation, 291–687 g CO 2 -eq (34%–62%) reduction can be achieved per kWh of power generated. The central tendency in each study is aligned more closely than the overall uncertainty range: thus, uncertainty caused by fundamental data challenges likely outweighs variability caused by use of different LCA methods. Differences in assumptions and methods among the three teams lead to moderate variation at the stage level, but in better agreement at the life-cycle level, showing the existence of compensating variation. Given the robustness to very different LCA methods, existing literature variation may be explained by project-, location- and operator-dependent parameters. • Three independent LCAs on the same LNG system using different methods and assumptions. • Large GHGs mitigation by displacing Chinese coal with Canadian LNG for power/heat generation. • Methods variation has less impact on life-cycle results than location- and operation-dependent factors. • Using both industrial and literature data can enhance the robustness of the life-cycle results. [ABSTRACT FROM AUTHOR]

Natural gas (NG) produced in Western Canada is a major and growing source of Canada's energy and greenhouse gas (GHG) emissions portfolio. Despite recent progress, there is still only limited understanding of the sources and drivers of Western Canadian greenhouse gas (GHG) emissions. We conduct a case study of a production facility based on Seven Generation Energy Ltd.'s Western Canadian operations and an upstream NG emissions intensity model. The case study upstream emissions intensity is estimated to be 3.1-4.0 gCO 2 e/MJ NG compared to current best estimates of British Columbia (BC) emissions intensities of 6.2-12 gCO 2 e/MJ NG and a US average estimate of 15 gCO 2 e/MJ. The analysis reveals that compared to US studies, public GHG emissions data for Western Canada is insufficient as current public data satisfies only 50% of typical LCA model inputs. Company provided data closes most of these gaps (∼80% of the model inputs). We recommend more detailed data collection and presentation of government reported data such as a breakdown of vented and fugitive methane emissions by source. We propose a data collection template to facilitate improved GHG emissions intensity estimates and insight about potential mitigation strategies.