Evolution of the life cycle primary PM2.5 emissions in globalized production systems.

Production system-related air pollution emissions are dominant components in global emission reduction targets and in realizing relevant sustainable development goals (SDGs). To better understand the air pollution emissions induced by globalized production systems through a life cycle perspective, environmental extended multiregional input-output (EE-MRIO) analysis was applied to calculate the primary product-based emissions and the final product-based emissions embodied in the global production systems. Combined with two types of linkage analysis, named the hypothetical extraction method (HEM) and the emissions pure backward linkage (EPBL), emissions were analysed at three scopes at the sector level from macro sector linkage perspectives. An illustrative analysis was presented based on the global EXIOBASE MRIO database and primary PM2.5 emissions from 1995 to 2011. The results show that from 1995 to 2011, the primary PM2.5 emissions in the global production systems increased by 35%. In 2011, China's production system generated the highest primary product-based and final product-based primary PM2.5 emissions, which accounted for 30.7% and 29.6% of the global total, respectively. The emission flows balance between primary product-based emissions and final product-based emissions revealed that most developing countries are sources of emissions and that developed countries are sinks of emissions in production systems. An approximately U-shaped relationship was found in the primary PM2.5 emissions embodied in final products, while the opposite relationship was found embodied in primary products. Meanwhile, sector-specific protocols for controlling the high indirect emissions sectors can make the supply chain cleaner. Our findings further indicated that focusing more on industries can help relevant emissions control policymaking processes.

Preventing graft restenosis after coronary artery bypass grafting with tissue-type plasminogen activator.

OBJECTIVE: To explore the feasibility and safety of using tissue-type plasminogen activator (t-PA) to prevent graft restenosis after coronary artery bypass grafting (CABG). METHODS: In this prospective observational study, 37 patients underwent CABG between June 2009 and May 2013. These patients were grouped according to the anti-coagulation strategy after surgery: t-PA (n = 12) and conventional treatments (n = 25). In the t-PA group, the patients received acetylsalicylic acid (ASA) and clopidogrel plus intravenous infusion of t-PA (0.25 mg/kg/day) starting at 24 h after surgery and that lasted for 3 days. In the conventional group, the patients received only ASA and clopidogrel. 64-row spiral computed tomographic coronary angiography was performed at 1 week, 1, and 3 months after surgery to evaluate the patency of the graft vessel. RESULTS: The mean stenosis severity of the saphenous vein grafts was lower in the t-PA group compared with the conventional group at 3 months after surgery (p < 0.05), but there was no significant difference at 1 week and 1 month (p > 0.05). The patency rate of the grafts was not significantly different between the two groups at 1 week, 1, and 3 months after surgery (p > 0.05). CONCLUSION: Early application of t-PA after CABG was feasible and safe, and might help prevent early restenosis of SV grafts. Additional clinical randomized trials are necessary to address this issue.

Establishment of an animal model of vascular restenosis with bilateral carotid artery grafting.

BACKGROUND: Vascular restenosis occurring after CABG is a major clinical problem that needs to be addressed. Vein grafts are associated with a higher degree of stenosis than artery grafts. However, the mechanism responsible for this effect has not been elucidated. We aimed to establish a rabbit model of vascular restenosis after bilateral carotid artery grafting, and to investigate the associated spatiotemporal changes of intimal hyperplasia in carotid artery and jugular vein grafts after surgery. MATERIAL AND METHODS: Twenty adult New Zealand white rabbits (10 males; 10 females), weighing 2.0-2.5 kg, were obtained from the Experimental Animal Center of Southern Medical University, Guangzhou, China (License No.: scxk-Guangdong-2006-0015). We quantitatively analyzed intimal thickness, area, and degree of stenosis in carotid artery and jugular vein bridges. RESULTS: After 8 weeks of a high-fat diet, rabbit carotid arteries showed early atherosclerotic lesions. With increasing time after surgery, carotid artery and jugular vein grafts showed histopathological and morphological changes, including smooth muscle cell migration, lipid deposition, intimal hyperplasia, and vascular stenosis. The degree of vascular stenosis was significantly higher in vein grafts than in artery grafts at all time points - 35.1±6.7% vs. 16.1±2.6% at Week 12, 56.2±8.5% vs. 23.4±3.4% at Week 16, and 71.2±1.3% vs. 25.2±5.3% at Week 20. CONCLUSIONS: Rabbit bilateral carotid arteries were grafted with carotid artery and jugular vein bridges to simulate pathophysiological processes that occur in people after CABG surgery.

[Comparative study on the quality of life in patients with prevertebral or retrosternal reconstruction after cervical tubular gastroesophagostomy].

OBJECTIVE: To compare the quality of life in patients with prevertebral or retrosternal reconstruction after cervical tubular gastroesophagostomy. METHODS: A total of 167 patients enrolled in this prospective study from July 2008 to June 2012 in Shantou Central Hospital, and divided into prevertebral route group(85 cases) and retrosternal route group(82 cases) according to the random number table method. Quality of life questionnaire was investigated 1, 3, 6, 9, and 12 months after operation respectively. RESULTS: The incidence of anastomotic stenosis was lower in the prevertebral route group (P<0.05). However, the differences in perioperative general conditions between the two groups were not statistically significant(all P>0.05). One hundred and forty-nine patients completed the postoperative quality of life questionnaire. Dysphagia and swallowing retching symptom were better, while acid reflux and heartburn symptom were more serious in prevertebral route group as compared to retrosternal route group(all P<0.05). Overall quality of life score difference between the two groups was not statistically significant(P>0.05). CONCLUSIONS: For digestive tract reconstruction after resection of esophageal cancer, tubular gastroesophagostomy by prevertebral or retrosternal route both can obtain better quality of life after surgery. Swallowing function after surgery of the former is superior to the latter, but the reflux symptoms is more serious. Therefore the two mehods have their own advantages and disadvantages, and the choice of route should be depended on clinical experience and patient condition.

ECM-related gene expression profile in vascular smooth muscle cells from human saphenous vein and internal thoracic artery.

UNLABELLED: Currently, Saphenous vein (SV) and internal thoracic artery (ITA) are still the most common graft materials in Coronary Artery Bypass Grafting (CABG) whereas SV graft have a lower long-term patency than ITA. Vascular smooth muscle cells (VSMCs) phenotype conversion, proliferation and migration may play a key role in mechanism of vein graft restenosis. To explore differential gene expression profile in VSMCs from SV and ITA will help to further elucidate the mechanism of VSMCs in vein graft restenosis after CABG and to provide new thread of gene therapy. METHODS: VSMCs from paired SV and ITA were cultured for experiments of Affymetrix microarrays and verification using FQ RT-PCR, while the database for annotation, visualization and integrated discovery bioinformatics resources (DAVID 2.0) was utilized for bioinformatics analysis of differential gene expression profile between SV VSMCs and ITA VSMCs. RNA of tunica media from SV and ITA segments were extracted for FQ RT-PCR to display differential expression of PLAT RESULTS: 54,613 probe sets were examined by gene microarray experiments. In SV VSMCs, 1,075 genes were up-regulated and 406 of them were higher than two-fold; 1,399 genes were down-regulated and 424 of them were lower than two-fold as compare with ITA VSMCs.14 ECM-related genes differentially expressed were verificated and listed as following: COL4A4, COL11A1, FN1, TNC, THBS, FBLN, MMP3, MMP9, TIMP3, WNT5A, SGCD were higher whereas COL14A1, ELN, PLAT lower in SV VSMCs than ITA VSMCs. In addition, PLAT was lower in tunica media from SV segments than ITA. CONCLUSION: VSMCs from SV and ITA have distinct phenotypes characteristics. Both promoting and inhibiting migration ECM-related genes were higher in VSMCs from SV as compared with ITA, suggesting that VSMCs from SV have more potential migrating capability whereas less PLAT both in SV VSMCs and vascular tissue,implying that SV may prone to be restenosis after CABG.