Methylmercury chloride damage to the adult rat hippocampus cannot be detected by proton magnetic resonance spectroscopy

Previous studies have found that methylmercury can damage hippocampal neurons and accord- ingly cause cognitive dysfunction. However, a non-invasive, safe and accurate detection method for detecting hippocampal injury has yet to be developed. This study aimed to detect methylmercury-induced damage on hippocampal tissue using proton magnetic resonance spectroscopy. Rats were given a subcutaneous injection of 4 and 2 mg/kg methylmercury into the neck for 50 consecutive days. Water maze and pathology tests confirmed that cognitive function had been impaired and that the ultrastructure of hippocampal tissue was altered after injection. The results of proton magnetic resonance spectroscopy revealed that the nitrogen-acetyl aspartate/ creatine, choline complex/creatine and myoinositol/creatine ratio in rat hippocampal tissue were unchanged. Therefore, proton magnetic resonance spectroscopy can not be used to determine structural damage in the adult rat hippocampus caused by methylmercury chloride.

支气管动脉栓塞术前行多层螺旋CT血管成像及图像分析对治疗咯血的应用价值

目的评估支气管动脉栓塞术前行多层螺旋CT血管成像(multidetector computed tomography angiography,MDCTA)及图像分析对治疗咯血的应用价值。方法回顾性分析2017年8月至2021年6月在襄阳市中心医院放射介入室行支气管动脉栓塞术的咯血患者165例,将其分为MDCTA组88例[有术前MDCTA,其中男63例,女25例,年龄23~87(62.6±12.3)岁]及对照组77例[男52例,女25例,年龄26~83(59.8±12.7)岁],比较两组患者的支气管动脉数、非支气管体循环动脉数及止血成功率等。组内比较采用配对设计定量资料的t检验或非参数配对Wilcoxon检验,组间比较采用两独立样本均数的t检验或非参数独立样本Mann-WhitneyU检验,组间比较采用上卡方检验。结果MDCTA组术中找到的原位和异位支气管动脉数分别显著高于对照组[(1.77±0.72)支比(1.42±0.82)支,t=2.98,P=0.003;0(0,0)支比0(0,0)支,Z=-2.13,P=0.033];MDCTA组中,MDCTA找到的原位和异位支气管动脉数分别显著高于术中找到的[(2.22±0.63)支比(1.77±0.72)支,Z=-4.73,P<0.001;0(0,0)支比0(0,0)支,Z=-2.81,P=0.005];MDCTA组中MDCTA找到的非支气管体循环动脉中的非肋间动脉数显著高于对照组术中找到的[0(0,0)支比0(0,0)支,Z=-2.07,P=0.038];MDCTA组止血成功率明显高于对照组(88.6%比68.8%,χ2=9.85,P=0.002)。结论支气管动脉栓塞术前行MDCTA及图像分析可帮助医生在术中找到更多的原位支气管动脉和异位支气管动脉数,并明显提高止血成功率。