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1.
Huan Jing Ke Xue ; 45(3): 1293-1303, 2024 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-38471846

RESUMO

Electrification of bus fleets is an effective approach to reducing transportation-related pollution and carbon emissions. Evaluating the impact of electrification on existing bus fleets can provide valuable insights for promoting full electrification of public transportation in large cities. Utilizing the fuel life cycle method, we analyzed the CO2 and pollutant emissions of Zhengzhou's bus fleet before and after electrification and evaluated emissions under different electrification scenarios. Our results indicated that after electrification, the fuel life cycle CO2 and PM2.5 emissions increased by 32.6% and 42.6%, respectively, whereas CO, NOx, and VOC emissions decreased by 28%, 34%, and 25%, respectively. Optimizing the power generation structure is a critical factor in reducing CO2 and PM2.5 emissions during the electrification process. The best scenario for comprehensive electrification and power generation structure optimization could result in a 38.7% reduction in CO2, as well as reductions of 80.1% in CO, 84.4% in NOx, 92.2% in VOC, and 30.2% in PM2.5. Prioritizing electrification on long-distance routes is recommended during the replacement process. Additionally, replacing plug-in hybrid natural gas vehicles with pure electric vehicles has both advantages and disadvantages in terms of emission reduction. Achieving pollution reduction and carbon synergies requires advancing fleet replacement and power structure adjustments simultaneously.

2.
Coron Artery Dis ; 31(1): e67-e72, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34010192

RESUMO

BACKGROUND: The optimal strategy of percutaneous coronary intervention (PCI) for isolated left anterior descending (LAD) ostial lesions remains debatable. This study aimed to compare clinical outcomes of patients with isolated LAD ostial stenosis treated by single-stent crossover versus accurate ostial stenting. METHODS: A total of 216 eligible consecutive patients with isolated de novo LAD ostial stenosis were enrolled, and were stratified according to the stenting techniques. Clinical follow-up was performed by review of medical charts or telephone contact with the patients, and repeat angiography was made at 9-12 months after the procedure. Major adverse cardiovascular events (MACE) including cardiac death, myocardial infarction, non-fatal stroke and target vessel revascularization (TVR) were recorded. RESULTS: Single-stent crossover and accurate ostial stenting were applied to 78 (36%) and 138 (64%) patients, respectively. During a mean of 13 ± 4.1 months of follow-up, the rate of composite MACE (19.6 vs. 8.9%; P = 0.040) was higher in LAD ostial stenosis patients treated with accurate ostial stenting than those treated with single-stent crossover technique, mainly driven by more frequent TVR (17.4 vs. 7.7%; P = 0.048). PCI strategy was an independent predictor of MACE (hazard ratio 2.561; 95% CI, 1.041-6.299; P = 0.021) in the multivariable Cox regression analysis. CONCLUSIONS: Our retrospective study suggests that the single-stent crossover technique is associated with a better 1-year clinical outcome compared with accurate ostial stenting in patients with isolated LAD ostial stenosis.


Assuntos
Stents/normas , Rigidez Vascular/fisiologia , Idoso , Angiografia Coronária/métodos , Estenose Coronária/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Intervenção Coronária Percutânea/métodos , Estudos Retrospectivos , Stents/estatística & dados numéricos , Resultado do Tratamento
3.
Huan Jing Ke Xue ; 41(7): 3056-3065, 2020 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-32608877

RESUMO

To understand the characteristics and potential hazards of volatile organic compounds (VOCs) emitted from different industrial factories in Zhengzhou, several representative factories have been selected for sample collection using canisters; the samples were subsequently analyzed by GC-MS/FID system, from which the composition and risk of VOCs are discussed in this study. It was found that OVOCs, especially ethyl acetate and isopropanol, were the most important species originating from printing factories, which accounted for more than 93.1% of total VOCs. The major components related to manufacturing industries, including automobile, furniture, and coating, were aromatics, mainly m/p-xylene, o-xylene, and ethylbenzene, which contributed 33.5%-90.0% to VOCs. Halogenated hydrocarbons made the largest contribution (52.3%) to VOCs in the food processing industry. The main components of VOCs were halogenoalkanes (25.5%) and alkanes (28.8%) in rubber factories. As for graphite carbon factories, the main components of VOCs were aromatics (28.5%) and alkanes (24.1%). Compared with previous studies, the VOC emission characteristics of factories involving solvent usage in Zhengzhou are consistent with those in other cities, but the compositional information of VOCs varies across different factories, even within the same industry, due to the different production processes and raw materials used. Risk assessment showed that the concentration of VOCs emitted from solvent factories are positively correlated with ozone formation potential (OFP) and the hazard index (HI). Specifically, benzene, toluene, ethylbenzene, xylene, and other C6-C8 aromatic hydrocarbons contributed significantly to OFP and HI. The HI values were 1.18 and 2.74 in automobile manufacturing factory NO.3 and wooden furniture factory NO.5, respectively, which were higher than the limits stated by EPA regulations because of the different production processes and raw materials, and the VOCs of the factories were mainly composed of aromatics; in particular, C6-C9 benzene series contributed significantly to HI and OFP. Therefore, it is necessary to control VOCs originating from industries involving solvent usage.


Assuntos
Poluentes Atmosféricos/análise , Compostos Orgânicos Voláteis/análise , Cidades , Monitoramento Ambiental , Medição de Risco
4.
Am J Physiol Renal Physiol ; 310(6): F511-7, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26764205

RESUMO

It is thought that carbamylated modification plays a crucial role in the development and progression of cardiovascular disease (CVD) in patients with end-stage renal disease (ESRD). However, information on the biological effects of carbamylated high-density lipoprotein (C-HDL) in ESRD is poor. The present study investigated the carbamylation level of HDL in ESRD and the effects of C-HDL on endothelial repair properties. HDL was isolated from healthy control subjects (n = 22) and patients with ESRD (n = 30). The carbamylation level of HDL was detected using ELISA. Isolated C-HDL for use in tissue culture experiments was carbamylated in vitro to a similar extent to that observed in ESRD. Human arterial endothelial cells were treated with C-HDL or native HDL to assess their migration, proliferation, and angiogenesis properties. HDL-associated paraoxonase 1 activity was also determined by spectrophotometry assay. Compared with healthy control subjects, the carbamylation level of HDL in ESRD patients was increased and positively correlated with blood urea concentration. In vitro, C-HDL significantly inhibited migration, angiogenesis, and proliferation in endothelial cells. Mechanistic studies revealed that HDL-associated paraoxonase 1 activity was decreased and negatively correlated with the carbamylation level of HDL in ESRD patients. In addition, C-HDL suppressed the expression of VEGF receptor 2 and scavenger receptor class B type I signaling pathways in endothelial cells. In conclusion, the present study identified a significantly increased carbamylation level of HDL in ESRD. Furthermore, C-HDL inhibited endothelial cell repair functions.


Assuntos
Células Endoteliais/fisiologia , Falência Renal Crônica/sangue , Lipoproteínas HDL/metabolismo , Idoso , Arildialquilfosfatase/metabolismo , Estudos de Casos e Controles , Cianatos/metabolismo , Feminino , Humanos , Falência Renal Crônica/etiologia , Masculino , Pessoa de Meia-Idade , Receptores Depuradores Classe B/metabolismo , Transdução de Sinais , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
5.
Chin Med J (Engl) ; 119(14): 1176-81, 2006 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-16863609

RESUMO

BACKGROUND: Patients with end-stage renal disease have a high mortality from coronary artery disease, but the impact of moderate renal insufficiency on clinical outcomes after percutaneous coronary intervention (PCI) and the effect of drug-eluting stent implantation in these patients remain unclear. This study determined the long-term effect of moderate renal insufficiency on death and major adverse cardiac events (MACE) after stent based PCI and examined whether drug-eluting stent implantation could favourably influence clinical outcome. METHODS: Major adverse cardiac events and causes of mortality were determined for 1012 patients undergoing percutaneous intervention from January 1, 2002 to December 31, 2004 at Shanghai Ruijin Hospital. Based on estimated creatinine clearance levels, long term outcomes were compared between patients with estimated creatinine clearance < 60 ml/min (renal insufficiency group; n = 410) and those with estimated creatinine clearance > or = 60 ml/min (control group; n = 602). Subgroup analysis was also made for patients with renal insufficiency between drug eluting stent (n = 264) and bare metal stent implantation (n = 146) during PCI. RESULTS: During follow-up (average 17 months) after successful PCI, all causes of death (7.1% vs 2.3%, P < 0.01) and cardiac death (3.4% vs 1.0%, all P < 0.01) were significantly higher in renal insufficiency group than in control group. For patients with moderate renal insufficiency, drug-eluting stent implantation reduced significantly all causes of death (5.3% vs 10.9%, P < 0.05) and occurrence of major cardiac adverse events (15.1% vs 24.6%, P < 0.05) compared with bare metal stents. CONCLUSIONS: Moderate renal insufficiency is an important clinical factor influencing the mortality after PCI in patients with coronary artery disease and the use of drug-eluting stents should be the preferred therapy for the improvement of long-term outcomes in such patients.


Assuntos
Angioplastia Coronária com Balão , Insuficiência Renal/mortalidade , Stents , Idoso , Angiografia Coronária , Sistemas de Liberação de Medicamentos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade
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