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131.
《Annales de cardiologie et d'angeiologie》2015,64(4):285-291
IntroductionAtrial fibrillation (AF) is the most common arrhythmia and is associated with significant morbidity and mortality. The impact of matrix metalloproteinases (MMPs) on structural atrial remodeling and sustainment of AF in patients with persistent and permanent AF is unresolved.ObjectivesThe aim was to evaluate MMP-9 and its tissue inhibitor-1 (TIMP-1) as markers of atrial remodeling in patients with persistent AF (PAF) who underwent electrical cardioversion (ECV) and in patients with permanent AF (continuous AF, CAF).Patients and methodsPlasma levels of MMP-9 and TIMP-1, clinical findings, and echocardiographic parameters were evaluated in 39 patients with AF and in 14 controls with sinus rhythm.ResultsThe concentrations of MMP-9 were significantly higher in patients with PAF and CAF compared to controls. There was a significant increase of MMP-9 after ECV in the persistent AF group. The values of TIMP-1 were not significantly different between the groups. In patients with AF, MMP-9 levels were positively related to posterior wall thickness of the LV (r = 0.356, P = 0.049) and body mass index (r = 0.367, P = 0.046).ConclusionElevated levels of MMP-9 were related to the occurrence and maintenance of AF. This suggests that MMP-9 can be a marker of atrial remodeling in patients with AF. Regulation of the extracellular collagen matrix might be a potential therapeutic target in AF. 相似文献
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心房颤动(简称房颤)是临床上最常见的持续性快速心律失常之一,可以引起心房内血栓、脑栓塞等严重并发症,是我国70岁以上老年人发病率较高、致死率较高的一种疾病。房颤的发生机制较为复杂,大量研究表明,心脏离子钾通道重构在房颤的发生和持续存在中发挥极其重要的作用。作用靶点位于钾离子通道的药物已应用于心房颤动,虽有一定的疗效但仍存在效果欠佳,并发症较多等缺点,现阶段关于心房钾离子通道重构及新型钾离子通道药物已经成为房颤研究中的热点之一。 相似文献
135.
《International journal of hygiene and environmental health》2014,217(2-3):323-327
Exposure to cadmium is known to be associated with reducing nitric oxide (NO) production in experimental conditions, but few studies have examined the association between environmental cadmium exposures and exhaled NO in human. We examined the association between blood cadmium levels and exhaled NO levels in a representative sample of US adults. This investigation was a cross-sectional study of 7813 adults (≥20 years) who participated in the 2007–2008 and 2009–2010 National Health and Nutrition Examination Survey and had their exhaled NO and blood cadmium measurements recorded. The geometric means of the exhaled NO and blood cadmium levels were 13.3 ppb (95% CI: 12.7, 13.9) and 0.51 μg/dL (95% CI: 0.48, 0.54), respectively. Higher blood cadmium levels were associated with decreased exhaled NO levels after adjusting for potential confounding variables. Additionally, a two-fold increase in the blood cadmium levels was associated with a 5% decrease in the exhaled NO levels. The results were significant regardless of the subjects’ smoking status or serum cotinine levels, although the percent changes in the exhaled NO levels differed depending on the extent of smoking.Our findings suggest that blood cadmium levels may be associated with reduced levels of exhaled NO in a general sample of US adults. Moreover, cadmium may partially mediate the effect of smoking on exhaled NO production. 相似文献
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目的观察一次性病毒/细菌过滤器在气管插管全麻术中预防气道感染的应用价值,为临床预防策略的制定提供参考。方法选择2011年3月-2013年3月接受气管插管全麻手术的患者76例,按照随机数字表法将其分为观察组和对照组各38例;观察组应用一次性病毒/细菌过滤器,而对照组则未用,分别在麻醉前和手术结束时用无菌棉签采集麻醉机呼气端、吸气端表面标本行细菌学检测;在手术结束时收集钠石灰罐底部10g钠石灰行细菌学检测,对比两组患者的检测结果和术后24h内气道感染发生率。结果两组患者在麻醉开始前麻醉机呼气端、吸气端细菌学培养结果均为阴性;手术结束时,麻醉机吸气端、呼气端和钠石灰的细菌学培养阳性率均为0,对照组分别为5.26%、42.11%和15.79%,观察组细菌培养阳性率均显著低于对照组,差异有统计学意义(P<0.05);术后24h内气道感染发生率观察组为2.63%,显著低于对照组的18.62%,差异有统计学意义(P<0.05)。结论麻醉机气管插管全麻可增加患者气道感染的机会,通过一次性病毒/细菌过滤器、及时更换钠石灰等措施,可有效预防气道感染的发生。 相似文献
138.
Anindita Dutta Sanghita Roychoudhury Saswati Chowdhury Manas Ranjan Ray 《International journal of hygiene and environmental health》2013,216(3):301-308
To perform sputum analysis for verification of pulmonary changes in premenopausal rural Indian women chronically exposed to biomass smoke during cooking.Three consecutive morning sputum samples were collected from 196 women (median age 34 years) cooking with biomass and 149 age-matched control women cooking with cleaner fuel liquefied petroleum gas. Smears made on slides were stained with Papanicolaou and Perl's Prussian blue. Airway oxidative stress was estimated as reactive oxygen species (ROS) generation (by flow cytometry) and superoxide dismutase (SOD) level (by spectrophotometry) in sputum cells. Airway inflammation was measured as sputum levels of interleukin (IL)-6, -8 and tumor necrosis factor- alpha (TNF-α). Particulate matter of diameter less than 10 (PM10) was measured using laser photometer while benzene exposure was monitored by measuring trans, trans-muconic acid (t,t-MA) in urine by HPLC-UV. Compared with control, sputum of biomass users contained more neutrophils, lymphocytes, eosinophils, alveolar macrophages, and showed presence of ciliocytophthoria, Charcot-Leyden crystals, Curschmann's spiral. ROS generation was increased by 2-fold while SOD was depleted by 31% in biomass users. They also had higher sputum levels of IL-6, -8 and TNF-α. Levels of PM10 and t,t-MA were 2.9- and 5.8-times higher in biomass-using women. PM10 and t,t-MA levels were positively associated with cellular changes in the sputum, markers of airway inflammation, and oxidative stress. Cooking with biomass alters sputum cytology, and increases airway inflammation and oxidative stress that might result in further amplification of the tissue damaging cascade in women chronically exposed to biomass smoke. 相似文献
139.
Chairs Louis-Philippe Boulet Qutayba Hamid Co-authors of sections of the document Simon L Bacon C��line Bergeron Louis-Philippe Boulet Yue Chen Anne E Dixon Pierre Ernst Qutayba Hamid Fernando Holguin Charles G Irvin R John Kimoff Sushma Komakula Catherine Laprise Kim L Lavoie Stephanie A Shore Mihaela Teodorescu Marie-Claude Vohl 《Canadian respiratory journal》2007,14(4):201-208
Asthma and obesity are frequently associated, and obesity has been considered a factor contributing to both an increase in severity of asthma and to its development. The present document summarizes the proceedings of a symposium held in Montreal, Quebec, on November 2, 2006, under the auspices of the Réseau en santé respiratoire du Fonds de la recherche en santé du Québec in collaboration with the McGill University – Strauss Severe Asthma Program, Université Laval (Quebec City) and Université de Montréal. It includes an overview of the various aspects of the relationships between asthma and obesity with regard to animal models; genetic, hormonal and physiological determinants; influence of comorbidities (eg, sleep apnea syndrome); epidemiology; clinical and psychological features; and management of asthma in the obese population. 相似文献
140.
Jeff SW Wong Calvin SH Ng Tak Wai Lee Anthony PC Yim 《Canadian respiratory journal》2006,13(4):219-221
The present report describes a case of severe airway obstruction caused by endobronchial tuberculosis in an 11-year-old girl who was successfully treated by bronchoscopic balloon dilation. This case illustrates the insidious presentation and the increasingly important role of bronchoscopic intervention in the management of endobronchial tuberculosis. In addition, a brief literature review of the condition in the pediatric age group is included. 相似文献