Three-dimensional microstructural changes in murine abdominal aortic aneurysms quantified using immunofluorescent array tomography

This study investigated the spatial and temporal remodeling of blood vessel wall microarchitecture and cellular morphology during abdominal aortic aneurysm (AAA) development using immunofluorescent array tomography (IAT), a high-resolution three-dimensional (3D) microscopy technology, in the murine model. Infrarenal aortas of C57BL6 mice (N=20) were evaluated at 0, 7, and 28 days after elastase or heat-inactivated elastase perfusion. Custom algorithms quantified volume fractions (VF) of elastin, smooth muscle cell (SMC) actin, and adventitial collagen type I, as well as elastin thickness, elastin fragmentation, non-adventitial wall thickness, and nuclei amount. The 3D renderings depicted elastin and collagen type I degradation and SMC morphological changes. Elastin VF decreased 37.5% (p<0.01), thickness decreased 48.9%, and fragmentation increased 449.7% (p<0.001) over 28 days. SMC actin VF decreased 78.3% (p<0.001) from days 0 to 7 and increased 139.7% (p<0.05) from days 7 to 28. Non-adventitial wall thickness increased 61.1%, medial nuclei amount increased 159.1% (p<0.01), and adventitial collagen type I VF decreased 64.1% (p<0.001) over 28 days. IAT and custom image analysis algorithms have enabled robust quantification of vessel wall content, microstructure, and organization to help elucidate the dynamics of vascular remodeling during AAA development.     

Decreased levels of inflammatory cytokines in immunoglobulin-resistant Kawasaki disease after plasma exchange

The pathogenesis of coronary artery aneurysm (CAA) formation in Kawasaki disease (KD) remains unknown. However, inflammatory cytokines are thought to play an important role in KD. Patients with intravenous immunoglobulin (IVIG)-resistant KD are more likely to develop CAA. For such refractory patients, steroids and emerging infliximab (IFX) are used; however, further verification is required for their efficacy and safety. Plasma exchange (PE), which removes various inflammatory cytokines, has been used in Japan for over 15 years to prevent CAA in IVIG-resistant KD patients. The sequential change in inflammatory cytokines during the time course of PE has yet to be investigated. In this study, we measured plasma levels of 13 cytokines in nine children with IVIG-resistant KD before the start of PE (day 0: D0), as well as at 1 or 2 days (D1/2), and 4 or 5 days (D4/5) after starting PE. The median age of onset was 8 months (range: 3–53 months). Before PE, patients were treated with IVIG (median dose: 4 g/kg, range: 3–4 g/kg). The median starting period of PE was 8 days after the onset of fever (range: 6–21 days), while its duration was 3 days (range: 2–5 days). Among the 13 cytokines, interleukin-6, tumor necrosis factor-α, tumor necrosis factor receptor I (TNFR1), TNFR2, granulocyte colony-stimulating factor, and IL-17 were significantly lower at D4/5 compared with D0 and/or D1/2, reflecting the potential central efficacy of PE. While three patients developed moderate CAA, their condition regressed within 1 year. The removal of inflammatory cytokines could be the central efficacy of PE against refractory KD.     

基质金属蛋白酶3、9在升主动脉瘤中的表达

目的探讨基质金属蛋白酶3、9(MMP-3、MMP-9)在升主动脉瘤发病机制中的作用.方法将40只幼年Wistar大鼠随机分为对照组和实验组,制备升主动脉缩窄鼠模型.于术后3-5个月取升主动脉,采用HE染色和免疫组化技术,观察升主动脉形态学变化及MMP-3、MMP-9的蛋白表达.结果升主动脉瘤中MMP-3、MMP-9表达强阳性.结论 MMP-3、MMP-9在升主动脉瘤成因中有可能有重要作用.     

Comparison of physiological and post-endovascular aneurysm repair infrarenal blood flow

Endovascular aneurysm repair (EVAR) of abdominal aortic aneurysms results in redirection of blood through the deployed endograft (EG). Even though EVAR is clinically effective, the absolute flow restoration is not warranted. Our purpose was to compare the physiological with the post-EVAR infrarenal flow conditions. We developed patient-specific models based on computed tomography data of five healthy volunteers and ten patients treated with the Endurant^® stent-graft system. Wall shear stress (WSS), helicity, pressure and velocity fields were calculated using computational fluid dynamics. The results showed a decrease of peak WSS on the part of the EG that resides in the iliac arteries, compared to the physiological value (p = 0.01). At the abdominal part, the average helicity seems to increase after EVAR, while at the iliac arteries part, the intensity of helical flow seems physiological. Pressure drop and peak velocity in the iliac arteries part are lower than the physiological values (p = 0.04). The comparison revealed that most hemodynamic properties converge to normal levels at the abdominal part whereas statistically significant variations were observed in the iliac arteries part. The delineation of the differences between physiological and postoperative flow data could pave the way for the improvement of EG designs.     

The distal aorta in the Marfan syndrome

Prolonged survival of patients with Marfan syndrome after aortic root replacement has led to an increased number of patients with aortic complications beyond the root. Elective replacement of the aortic root removes the most important predilection site for aneurysms, but the distal aorta remains at risk. Predictors for aortic growth and adverse events in the distal aorta include aortic diameter, aortic distensiblity, previous aortic root replacement, hypertension and aortic regurgitation. After aortic dissection, the initial false lumen diameter is an independent predictor for late aneurysm formation. Although there are a few reports of short-term success after endovascular stent grafting of the descending thoracic aorta, stent grafting in patients with Marfan syndrome is not recommended unless intervention is clearly indicated and the risk of conventional open surgical repair is deemed prohibitive. Optimal long-term outcome demands lifelong radiographic follow-up and medical treatment with β-blocker therapy. After aortic dissection rigorous antihypertensive medication is of utmost importance. Losartan, an angiotensin II type I receptor antagonist, might offer the first potential for primary prevention of clinical manifestations in Marfan syndrome, but the results of clinical trials have to be awaited. (Neth Heart J 2008;16:382-6.)     

The aetiologies of unilateral oculomotor nerve palsy: a clinical analysis on 121 patients

Background and purpose: To strengthen the understanding, increase the early diagnostic rate, and improve the outcome of unilateral oculomotor nerve palsy through the analysis of the 121 patients suffering from this disease in our hospital.

Methods: A retrospective study was performed on the 121 patients with unilateral oculomotor nerve palsy diagnosed at the Affiliated Hospital of Xuzhou Medical University from October 2014 to October 2015. The clinical data, such as gender, age, aetiology, clinical features, laboratory tests, and six months follow up reports were analyzed.

Results: The main causes identified in the 121 patients with unilateral oculomotor nerve palsy were intracranial aneurysm (29.8%), diabetic peripheral neuropathy (26.5%), painful ophthalmoplegia (9.9%), and other causes (33.9%). The results from the six month follow up showed that in all the patients, 53.7% were fully recovered, 38.0% improved, and 8.3% had no significant change in symptoms. The results also indicated that the patients with diabetic peripheral neuropathy had the best outcome with 71.9% full recovery rate, which was significantly higher than that in the patients with intracranial aneurysm (36.1%, p?<?.05), and idiopathic causes (44.5%, p?<?.05).

Conclusions: Our data indicates that intracranial aneurysm is the leading cause of unilateral oculomotor nerve palsy, and that diabetic peripheral neuropathy has better outcome. Understanding the common causes and clinical features of unilateral oculomotor nerve paralysis is helpful for its early diagnosis and treatment.     

介入栓塞对颅内动脉瘤患者动脉瘤破裂、神经及脑损伤相关因子的影响

目的:探讨介入栓塞对颅内动脉瘤患者动脉瘤破裂、神经及脑损伤相关因子的影响。方法:选择我院收治的98例颅内动脉瘤患者,随机分为观察组50例以及对照组48例。观察组应用血管内介入手术,对照组应用显微外科夹闭手术。观察比较两组治疗前后血清胱抑素C(Cys-C)、含半胱氨酸的天冬氨酸蛋白水解酶3(Caspase3)、神经元特异性烯醇化酶(NSE)、星形胶质源性蛋白(S100β)、白介素-6(IL-6)、内皮素-1(ET-1)及基质金属蛋白酶-9(MMP-9)水平的变化。结果:治疗前,两组各项指标水平无显著变化(P0.05);治疗后,两组血清Cys-C、Caspase3、IL-6、ET-1、MMP-9水平均较治疗前显著降低(P0.05),且观察组以上指标水平显著低于对照组(P0.05);而组间及组内前后血清NSE及S100β水平比较差异均无明显统计学意义(P0.05)。结论:采用介入栓塞治疗颅内动脉瘤患者可能会降低颅内动脉瘤发生破裂的可能性,降低脑损伤程度,且对中枢神经系统影响不大。     

Coupling between MRI-assessed regional aortic pulse wave velocity and diameters in patients with thoracic aortic aneurysm: a feasibility study

Aims

Thoracic aortic aneurysm (TAA) is potentially life-threatening and requires close follow-up to prevent aortic dissection. Aortic stiffness and size are considered to be coupled. Regional aortic stiffness in patients with TAA is unknown. We aimed to evaluate coupling between regional pulse wave velocity (PWV), a marker of vascular stiffness, and aortic diameter in TAA patients.

Methods

In 40 TAA patients (59 ± 13 years, 28 male), regional aortic diameters and regional PWV were assessed by 1.5 T MRI. The incidence of increased diameter and PWV were determined for five aortic segments (S1, ascending aorta; S2, aortic arch; S3, thoracic descending aorta; S4, suprarenal and S5, infrarenal abdominal aorta). In addition, coupling between regional PWV testing and aortic dilatation was evaluated and specificity and sensitivity were assessed.

Results

Aortic diameter was 44 ± 5 mm for the aortic root and 39 ± 5 mm for the ascending aorta. PWV was increased in 36 (19 %) aortic segments. Aortic diameter was increased in 28 (14 %) segments. Specificity of regional PWV testing for the prediction of increased regional diameter was ≥ 84 % in the descending thoracic to abdominal aorta and ≥ 68 % in the ascending aorta and aortic arch.

Conclusion

Normal regional PWV is related to absence of increased diameter, with high specificity in the descending thoracic to abdominal aorta and moderate results in the ascending aorta and aortic arch.