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1.
学者们对动脉血管的研究常聚焦在血管内膜动脉粥样硬化(As)斑块的形成,而很少关注血管外膜的免疫反应及其对疾病病程的影响。前期研究发现,老龄的ApoE-/-小鼠动脉外膜出现免疫细胞的有序集聚,形成类似淋巴结的异位淋巴组织,称之为动脉三级淋巴组织(ATLO),其形成对内膜As具有明显的调控作用。ATLO的发现及研究为As的研究指明了新的方向,并为其他疾病状况下三级淋巴组织(TLO)的研究提供了很好的范例。因此,阐明TLO的特点及形成机制对As的防治具有重要的意义,并为其在其他疾病中的临床运用提供坚实的基础。  相似文献   
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Vascular injuries that occur during traffic accidents are a commonly neglected aspect that can add more detail to the framework of a case. In this study, we analysed a case series of 150 traffic accidents, 39 of which were marked by microscopically identifiable vascular lesions. The purpose was to identify the presence of carotid injuries in individuals who died due to traffic accidents and had nonpenetrating trauma of the neck. We focused on the discrepancies regarding the macroscopical aspect and the histology and demonstrated how histological analysis of the carotids in cases of trauma can reveal injuries that are attributable to the trauma itself. We conducted a histological analysis of the lesions to describe their distribution and type and investigate potential correlations. The study offers insight on how to examine road accidents that involve traumatic injury of the carotid arteries. Indeed the main task of the forensic pathologist in the case of death is to establish the existence of a causal relationship between the micro- or macroscopic alterations observed in the autopsy and the traumatic event that led to the death of the subject. Thus, further morphological elements were provided to the forensic practitioners that may reveal injuries attributable to the trauma itself and should be evaluated in cases of trauma in traffic accidents.  相似文献   
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Invasive coronary plaque imaging such as intravascular ultrasound and optical coherence tomography has been widely used to observe culprit or non-culprit coronary atherosclerosis, as well as optimize stent sizing, apposition and deployment. Coronary computed tomographic angiography (CTA) is non-invasively available to assess coronary artery disease (CAD) and has become an appropriate strategy to evaluate patients with suspected CAD. Given recent technologies, semi-automated plaque software is available to identify coronary plaque stenosis, volume and characteristics and potentially allows to be used for the assessment of more details of plaque information, progression and future risk as a surrogate tool of the invasive imaging modalities. This review article aims to focus on various evidence in coronary plaque imaging by coronary CTA and describes how accurate coronary CTA can classify coronary atherosclerosis.  相似文献   
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Background and purposeMultiply occurring intracranial dural arteriovenous fistulas (dAVFs) have been documented but rarely occur, and neither pathogenesis nor prognosis is clearly understood. This study was conducted to analyze angiographic characteristics of multiple dAVFs and to chronicle our treatment experience.MethodsBetween April, 2002 and January, 2018, data prospectively collected from 310 patients with intracranial dAVFs were systematically reviewed, assessing clinical and anatomic outcomes of endovascular treatment in 32 patients with multiple dAVFs (≥ 2 fistulas each). Lesions were categorized as multifocal or diffuse type, depending on presentation, and further characterized as progressive or non-progressive disease.ResultsOverall, 18 patients (56.3%) experienced aggressive presentations, including intracerebral hemorrhage or venous infarction. Cortical venous reflux (CVR) was observed in 26 patients (81.3%), and sinus thrombosis or occlusion was seen in 24 (75.0%). Clinical outcomes in patients with multifocal fistulas (n = 11) were excellent (100%), marked by a moderately high rate of complete occlusion (54.5%). Those with progressive disease (n = 10) regularly displayed certain angiographic findings, namely diffuse configuration (100%), sinus thrombosis (100%), and CVR (100%). Complete anatomic obliteration was achieved in 12 patients (37.5%), and in 26 patients (81.3%), clinical outcomes were favorable.ConclusionMultiple dAVFs are typically aggressive at presentation, given strong associations with CVR and sinus thrombosis. In diffuse-type fistulas, the potential to recur or progress is high. Although definitive treatment poses a challenge, outcomes of endovascular therapeutics may be still optimized in this setting through strategic procedural modifications and careful follow-up monitoring.  相似文献   
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A pathological feature in atherosclerosis is the dysfunction and death of vascular endothelial cells (EC). Oxidized low‐density lipoprotein (LDL), known to accumulate in the atherosclerotic arterial walls, impairs endothelium‐dependent relaxation and causes EC apoptosis. A major bioactive ingredient of the oxidized LDL is lysophosphatidylcholine (LPC), which at higher concentrations causes apoptosis and necrosis in various EC. There is hitherto no report on LPC‐induced cytotoxicity in brain EC. In this work, we found that LPC caused cytosolic Ca2+ overload, mitochondrial membrane potential decrease, p38 activation, caspase 3 activation and eventually apoptotic death in mouse cerebral bEND.3 EC. In contrast to reported reactive oxygen species (ROS) generation by LPC in other EC, LPC did not trigger ROS formation in bEND.3 cells. Pharmacological inhibition of p38 alleviated LPC‐inflicted cell death. We examined whether heparin could be cytoprotective: although it could not suppress LPC‐triggered Ca2+ signal, p38 activation and mitochondrial membrane potential drop, it did suppress LPC‐induced caspase 3 activation and alleviate LPC‐inflicted cytotoxicity. Our data suggest LPC apoptotic death mechanisms in bEND.3 might involve mitochondrial membrane potential decrease and p38 activation. Heparin is protective against LPC cytotoxicity and might intervene steps between mitochondrial membrane potential drop/p38 activation and caspase 3 activation.  相似文献   
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动脉粥样硬化是临床常见的冠心病和脑梗死等缺血性心脑血管疾病的主要病理基础,其病因复杂,发病机制尚未完全阐明。近年来,越来越多的研究显示鞘磷脂类信号通路可通过调节脂代谢、炎症和血管内皮功能等影响动脉粥样硬化的发生发展。文章综述了鞘磷脂类信号通路关键分子鞘磷脂、神经酰胺和1-磷酸鞘氨醇与动脉粥样硬化的关系,旨在为防治疾病提供新思路。  相似文献   
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目的探讨颈动脉超声联合血清五聚素3(PTX3)、脂蛋白相关磷脂酶A2(Lp-PLA2)检测对动脉粥样硬化脑梗死的诊断价值。方法随机选择2015年1月至2017年12月在本院神经内科就诊的急性缺血性脑卒中患者56例作为观察组,选择同期在本院体检的健康者50例作为对照组。2组研究对象均行颈动脉超声检查,并采集静脉血检测PTX3、Lp-PLA2的水平。比较2组血清PTX3、Lp-PLA2水平及颈动脉内膜中膜厚度(IMT)增厚、斑块、中重度狭窄检出率。分析颈动脉超声、PTX3、Lp-PLA2单独及联合检测对动脉粥样硬化脑梗死的诊断价值。结果观察组血清PTX3、Lp-PLA2水平显著高于对照组(P0. 05),颈动脉IMT增厚、斑块、中重度狭窄检出率显著高于对照组(P0. 05)。颈动脉超声联合PTX3、Lp-PLA2检测的灵敏度、准确率为89. 29%、77. 36%,明显高于PTX3(73. 21%、71. 69%)、Lp-PLA2(69. 64%、67. 92%)及颈动脉超声(80. 36%、76. 42%)的单独检测结果(均P0.05)。ROC曲线显示,颈动脉超声检查的曲线下面积(AUC)为0. 789,PTX3检测的AUC为0. 764,Lp-PLA2检测的AUC为0. 776,而联合检测的AUC为0. 909,差异有统计学意义(P0. 05)。结论颈动脉超声联合血清PTX3、LpPLA2检测能够显著提高动脉粥样硬化脑梗死诊断的灵敏度和准确率。  相似文献   
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