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Background

Systemic inflammation and increased matrix metalloproteinase (MMP) cause elastin degradation leading to abdominal aortic aneurysm (AAA) expansion. Several prospective studies report that statin therapy can reduce AAA expansion through anti-inflammation. We hypothesize that monocyte activity plays a pivotal role in this AAA development and this study examines patient peripheral blood monocyte cell adhesion, transendothelial migration, and MMP concentrations between AAA and non-AAA patients.

Materials and methods

Peripheral blood was collected and monocytes isolated from control (n = 15) and AAA (n = 13) patients. Monocyte adhesion, transmigration, and permeability assays were assessed. Luminex assays determined MMP-9 and tissue inhibitor of metalloproteinase-4 (TIMP-4) concentrations from cell culture supernatant and patient serum.

Results

AAA patient monocytes showed increased adhesion to the endothelium relative fluorescence units (RFU, 0.33 ± 0.17) versus controls (RFU, 0.13 ± 0.04; P = 0.005). Monocyte transmigration was also increased in AAA patients (RFU, 0.33 ± 0.11) compared with controls (RFU, 0.25 ± 0.04, P = 0.01). Greater numbers of adhesive (R2 = 0.66) and transmigratory (R2 = 0.86) monocytes were directly proportional to the AAA diameter. Significantly higher serum levels of MMP-9 (2149.14 ± 947 pg/mL) were found in AAA patients compared with controls (1189.2 ± 293; P = 0.01). TIMP-4 concentrations were significantly lower in AAA patients (826.7 ± 100 pg/mL) compared with controls (1233 ± 222 pg/mL; P = 0.02). Cell culture supernatant concentrations of MMP and TIMP from cocultures were higher than monocyte-only cultures.

Conclusions

Monocytes from AAA patients have greater adhesion and transmigration through the endothelium in vitro, leading to elevated MMP-9 levels and the appropriate decrease in TIMP-4 levels. The ability to modulate monocyte activity may lead to novel medical therapies to decrease AAA expansion.  相似文献   
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Left ventricular (LV) pseudoaneurysm is a rare entity and, consequently, there is limited knowledge of the condition’s natural history. The most frequent mode of presentation for LV pseudoaneurysm is heart failure with chest pain. However, the variable presentation of this condition requires a high index of suspicion for diagnosis.We report the case of a 75-year-old woman who had suffered an acute myocardial infarction 23 years previously, which resulted in a calcified LV apical aneurysm. Three weeks prior to being referred to our hospital, she was noted by her general practitioner to have a left-sided breast mass although mammography was negative. One week later, she attended the accident and emergency department; she was haemodynamically unstable but was resuscitated successfully. Contrast enhanced computed tomography showed a large haematoma located in the left chest wall communicating with the left ventricle. She underwent emergency cardiac surgical repair. On arrival at the intensive care unit following surgery, her haemodynamic status was unstable, and she deteriorated rapidly and died.With this report, we aim to raise the level of awareness for an apical LV pulsatile mass that could anatomically expand and present as a breast mass or tumour. An early diagnosis and timely surgical intervention is essential in order to achieve better outcomes and avoid detrimental complications.  相似文献   
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目的:探索过滤伞在颈动脉狭窄支架成形术中的有效性和安全性。材料和方法:20例颈动脉狭窄行支架成形术患者,均采用过滤伞保护装置,术后短期随访。大体观察回收的过滤伞,观察围手术期间死亡、脑栓塞情况以及脑缺血事件的发生。结果:全部过滤伞成功放置,支架成形术均成功实施,回收的20个过滤伞中18个发现组织碎片,无手术死亡,无症状性脑血栓栓塞,临床短期随访均无脑缺血事件发生。结论:过滤伞能有效防止脑血栓事件的发生,在颈动脉狭窄支架成形术中是安全和有效的。  相似文献   
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