儿童急性坏死性脑病的影像学分析

目的分析儿童急性坏死性脑病(ANEC)的颅脑影像学特征,探讨其对临床的指导价值。方法回顾性分析2013年1月至2018年10月武汉儿童医院22例确诊为ANEC患儿的临床及影像资料。患儿病初均有高热,前驱感染后迅速出现神经功能恶化。首次影像检查中,所有患儿均行头颅MRI检查,其中6例MRI检查前行头颅CT检查。MRI随访中,4例失访,6例仅行1次短期随访(<14 d),12例接受1~2次短期及1~4次长期随访(>14 d)。影像学检查重点观察丘脑、脑干、脑白质和基底节区等部位,以及整个随访中是否有出血及软化灶形成。结果所有ANEC患儿的影像学表现中均累及双侧丘脑,其他对称病变部位包括大脑白质(14例)、基底节区(15例)、脑干(16例)、小脑(9例)、胼胝体(2例)和海马(1例),不对称病灶患儿3例,分别见于大脑白质(2例)及小脑(1例)。最典型的头颅MRI表现为急性期在表观扩散系数(ADC)图上,丘脑呈"三色模式"(中央高信号和周围低信号环,以及丘脑周围高信号)或"双色模式"(丘脑中央低信号及边缘高信号)。影像学随访中,MRI上出现出血、脑软化可能提示临床预后差。结论ANEC为快速进展型脑病,具有典型影像学特点,出血、脑软化可能提示不良预后。     

Experimental study on “ischemic memory” of myocardium with different ischemic degrees by 18 F-FDG PET/CT

Glucose metabolism and ranges of ischemic cardiomyocytes in model rats under fasting or feeding were compared by 18F-FDG PET/CT, respectively, to investigate the changes of glucose metabolism after myocardial reperfusion, and to determine time window of myocardial “ischemic memory” under feeding. The ischemic–reperfusion model rats were established by ligating the left anterior descending coronary artery of rats. In fasting–feeding experiment, long-ischemia rats (n = 10) under fasting or feeding were subjected to 18F-FDG PET/CT at 24 h after modeling. Ischemic myocardium range and glucose metabolism were compared by calculating volume of interest (VOI), and mean standard uptake value (SUVmean). Under feeding, model rats in short, intermediate and long-ischemia groups were subjected to 18F-FDG PET/CT at 24, 48, and 72 h and long-ischemia rats were also subjected to 18F-FDG PET/CT at 96 h, and VOI and SUVmean were calculated and compared. (1) Under fasting, myocardial ischemic area of model rats showed “focal” 18F-FDG uptake, while “focal” 18F-FDG uptake defect appeared in the same area of myocardium under feeding and the difference was not statistically significant (P > 0.05). (2) Under feeding, PET myocardial images of model rats in three groups at 24 h and 48 h showed that there was an 18F-FDG uptake defect area near the apex of left ventricular wall. The images at 72 h showed that there was no abnormal 18F-FDG uptake defect area in short and intermediate-ischemia groups, while 18F-FDG uptake defect area in long-ischemia group disappeared at 96 h. Variance analysis of repeated measures was performed for data of three groups, which showed there was statistical significance between myocardial ischemia degree and “ischemic memory” time window (P < 0.05), and also between myocardial ischemia degree and difference of myocardial defect volume (P < 0.05). Under feeding, recent myocardial ischemia could be diagnosed by 18F-FDG PET/CT. Under feeding, “ischemic memory” time window for short and intermediate-myocardial ischemia was at least 48 h and for long ischemia was at least 72 h. This study suggested that as the degree of myocardial ischemia increased, “ischemic memory” time window also extended.     

Application of scanning electron microscopy in the auxiliary diagnosis of death caused by potassium chloride intravenous injection: a case report

International Journal of Legal Medicine - To determine the cause of death, in addition to routine autopsy, some assisted techniques are imperative to achieve a definite diagnosis. Herein, we report...     

基于3D打印和CT三维重构数值模拟上呼吸道气流状态的研究方法

目的建立物理模型实验和数值模拟相结合的方法,用于研究上呼吸道气流状态。方法基于网上公开CT医学图像,重建人体上呼吸道三维模型。基于3D打印技术,建立上呼吸道实验模型,进行呼吸的流量过程测量实验;通过对上呼吸道三维模型进行网格划分,采用湍流Realizable k-ε数值模型进行计算。结果首先进行与实验工况对应的数值模拟对比研究,得到与实验吻合的结果。数值模拟结果表明,呼吸过程中的气流的流动轨迹呈抛物线形状,呼气和吸气阶段的流场、壁面压力和涡结构分布很大区别,呼吸交换过程中上下鼻道有空气残留。另外,通过脉线、压力分布和涡结构分布情况,初步分析气流对上呼吸道生理环境的影响。结论该方法具有针对性、快速性和准确性的特点,充分发挥了物理实验可靠和数值模拟精细的优点,适用于不同个案上呼吸道不同问题的研究,对临床个性化诊疗具有价值。     

Therapeutic potential of phenylethanoid glycosides: A systematic review

Phenylethanoid glycosides (PhGs) are generally water-soluble phenolic compounds that occur in many medicinal plants. Until June 2020, more than 572 PhGs have been isolated and identified. PhGs possess antibacterial, anticancer, antidiabetic, anti-inflammatory, antiobesity, antioxidant, antiviral, and neuroprotective properties. Despite these promising benefits, PhGs have failed to fulfill their therapeutic applications due to their poor bioavailability. The attempts to understand their metabolic pathways to improve their bioavailability are investigated. In this review article, we will first summarize the number of PhGs compounds which is not accurate in the literature. The latest information on the biological activities, structure–activity relationships, mechanisms, and especially the clinical applications of PhGs will be reviewed. The bioavailability of PhGs will be summarized and factors leading to the low bioavailability will be analyzed. Recent advances in methods such as bioenhancers and nanotechnology to improve the bioavailability of PhGs are also summarized. The existing scientific gaps of PhGs in knowledge are also discussed, highlighting research directions in the future.     

Thioredoxin-1 inhibitor PX-12 induces human acute myeloid leukemia cell apoptosis and enhances the sensitivity of cells to arsenic trioxide

Thioredoxin-1 (Trx-1), an important redox regulatory factor, plays a significant role in drug-induced apoptosis. Here we investigated the effects of the Trx-1 inhibitor 1-methylpropyl 2-imidazolyl disulfide (PX-12) on human acute myeloid leukemia cells (AML) and the sensitivity of cells to arsenic trioxide (As2O3, ATO). Treatment of cells with a different concentration of PX-12 for 48 h resulted in growth inhibition, the induction of apoptosis and increased the levels of activated caspase-3 expression in AML cell lines HL-60, NB4, U937 and primary AML cells in a dose-dependent manner. In addition, PX-12 enhanced the sensitivity of U937 cells to ATO. These results suggest the effects of Trx-1 inhibitor PX-12 to induce apoptosis in AML cells and therapeutic potential in AML by enhancing the sensitivity of cells to ATO.     

磁共振血管造影侧枝血管在卒中机械取栓术后预后中的应用价值

目的探讨磁共振血管造影(magnetic resonance angiography,MRA)中侧枝血管与急性卒中机械取栓术后预后间的关系。材料与方法前瞻性纳入接受机械取栓治疗的急性卒中患者。所有患者均于治疗前及治疗后24 h内接受头颅MRI平扫和MRA检查。3个月后的预后情况根据改良Rankin量表(modified Rankin Scale,mRS)评估,mRS0~2为预后良好组,mRS3~6为预后不良组。统计学方法分析预后良好组与不良组之间侧裂及软脑膜的侧枝血管的差异。结果共55例动脉闭塞的卒中患者纳入分析(侧裂侧枝血管不丰富者52例,软脑膜侧枝血管不丰富者45例)。侧裂血管和软脑膜血管不丰富的患者,预后良好组的入院NIHSS评分(10.06±4.65 vs 14.25±4.91;P=0.006)、术前梗死体积(13.61±10.99 vs 59.80±92.74;P=0.006)均低于预后不良组。多元逻辑回归分析显示年龄、软脑膜的侧枝循环是预测预后的独立预测因子(OR=1.094,95%CI=1.025~1.168,P=0.007;OR=9.542,95%CI=1.812~50.245,P=0.008)。预后良好组的梗死增长体积(术前vs术后:14.15±10.73 vs 21.39±17.41)小于预后不良组(术前vs术后:16.88±16.64 vs 57.27±56.67),然而多元逻辑回归分析显示术后梗死体积对预测卒中预后无显著意义(OR=1.094,95%CI=1.025~1.168,P=0.154)。结论磁共振血管造影侧枝血管可用于评估卒中预后,尤其是软脑膜的侧枝循环可预测卒中预后,而术后卒中梗死体积与预后的关系仍需进一步研究。     

基于网络药理学方法预测定喘汤治疗慢性阻塞性肺疾病的作用机制及验证研究

目的：分析定喘汤治疗慢性阻塞性肺疾病(COPD)的分子机制,并通过细胞实验验证定喘汤的药理学作用。方法：在中药系统药理学数据库与分析平台(TCMSP)数据库中,对定喘汤9味中药进行有效成分筛选,利用UniPort数据库得到中药活性成分相关靶点。随后在五大疾病数据库中以COPD作为关键词进行检索,收集疾病对应的靶点基因。对有效成分-交集靶点网络进行拓扑分析,根据中药有效成分与交集靶点之间连接情况筛选定喘汤治疗COPD关键成分。最后通过基因本体(GO)富集分析和京都基因和基因组百科全书(KEGG)富集分析确定定喘汤治疗机制并进行分子对接,从整体生物网络角度阐述定喘汤治疗COPD的免疫炎症机制,并通过细胞实验加以验证。结果：本实验筛选得到定喘汤274个活性成分,与疾病交集靶点262个。KEGG富集分析表明核心靶点作用于白细胞介素-17(IL-17)信号通路、NOD样受体信号通路及趋化因子信号通路等多种免疫和炎症反应相关的信号通路,分子对接显示核心化合物与靶点具有良好的对接活性。细胞实验表明,定喘汤能通过磷脂酰肌醇3激酶/蛋白激酶B(PI3K/AKT)信号通路,抑制人Ⅱ型肺泡上皮细胞炎症反应,...