冠状动脉斑块性质与冠周脂肪相关性的MRI研究进展

因冠状动脉斑块细小且随心脏不停跳动,MRI对冠状动脉粥样硬化斑块性质的评估一直是研究的难点之一。最新研究表明,冠周脂肪环境的变化与冠状动脉粥样硬化斑块性质密切相关。目前新的多模态磁共振成像技术能定量评估冠周脂肪环境变化,有望能有效评估冠状动脉斑块性质,因此研究冠周脂肪具有重要的临床意义。现从冠周脂肪的生物学意义、冠周脂肪评估的比较影像学及其影像学的临床应用等方面进展进行综述。

Research progress of magnetic resonance imaging on the correlation between coronary plaque properties and pericoronal fat

Because of the small size of coronary plaque and its continuous beating with the heart,the assessment of the nature of coronary atherosclerotic plaques by magnetic resonance imaging remains a challenge in current research.Recent studies have shown that changes in the pericoronary fat environment are closely related to the nature of coronary atherosclerotic plaques.At present,the new multi-modal magnetic resonance technology can quantitatively assess the changes of pericorral fat environment,which is expected to effectively evaluate the properties of coronary artery plaque.Therefore,it is of greater clinical importance to study pericoronary fat.Advances in the biological significance of pericoronary fat,comparative imaging for pericoronary fat assessment and clinical applications of its imaging will be reviewed.

小鼠脑出血后不同时间点小胶质细胞极化状态的实验研究

目的观察小鼠脑出血后不同时间点小胶质细胞M1及M2型的转化,为促炎型M1型小胶质细胞向抗炎修复型M2型小胶质细胞的转化,减轻脑出血后神经功能损伤提供理论依据。方法选取健康雄性ICR小鼠48只,随机分为假手术组、脑出血组,每组按术后时间点不同随机分为1 d、3 d、7 d三个时间点,每个时间点8只。通过立体定位仪用微量注射器向尾状核注射Ⅳ型胶原酶0.5 U制备脑出血模型,假手术组注射等量生理盐水。各组于术后对应时间点参照改良Garcia评分量表进行神经功能缺损评分后灌注取脑,采用蛋白免疫印迹检测M1型小胶质细胞标志物肿瘤坏死因子α(tumor necrosis factor-α,TNF-α)、白细胞介素6(interleukin-6,IL-6),M2型小胶质细胞标志物脑源性神经营养因子(brai n-derived neurotrophic factor,BDNF)、胰岛素样生长因子1(insulinlike growth factor 1,IGF-1)的含量;采用免疫荧光染色标记小胶质细胞M1型(Iba1+CD80)、M2型(Iba1+CD206),评价出血后血肿周围组织小胶质细胞活化状态。结果脑出血组1 d、3 d、7 d各时间点Garci a评分均较假手术组低,TNF-α、IL-6、BDNF及I GF-1的蛋白表达量均较假手术组增多(均P<0.01)。脑出血后1 d时M1型高于M2型小胶质细胞数量(38.33±1.53 vs 23.00±3.00,P=0.01);3 d时M1型同样高于M2型(66.33±3.06 vs 57.33±2.52,P=0.02);7 d时M1型低于M2型(33.67±1.15 vs 52.33±0.58,P<0.01)。结论脑出血急性期(1~3 d)以M1型小胶质细胞为主,脑出血亚急性期(7 d)以M2型小胶质细胞为主。