Patient clinical characteristics and outcome.

Background
Trace elements (TEs) status alterations in the brain have been linked to neurodegenerative diseases. However, data on TEs in living humans and in the post-traumatic conditions are scarce. Some TEs (copper – Cu, selenium – Se, zinc – Zn) are involved in essential antioxidant defence. This study aims to measure the evolution of TEs concentrations in the brain and serum of severe traumatic brain injury (TBI) patients over time.
Methods
Twenty adult patients with severe TBI were monitored using cerebral microdialysis (CMD) and blood sampling within three days of intensive care unit admission. TEs levels were measured using inductively coupled plasma system coupled to mass spectrometry.
Results
TEs concentrations of chromium – Cr, Cu, cobalt – Co, manganese – Mn, molybdenum – Mo, Se, and Zn were quantified in brain interstitial fluid and serum. While serum and CMD levels did not differ significantly for Co, Mo and Mn, and modest differences was observed for Cr and Zn, significant differences were observed for Cu and Se with higher serum levels (8–10-fold higher) compared to CMD. No correlation was found between serum and brain TEs levels, except for Mo.
Conclusion
This study provides novel TEs concentration data in living TBI patients, the largest differences between brain and serum being observed for Cu and Se, serving as a basis for further research on TEs dynamics in acute brain injury.

背景
脑内微量元素（Trace elements, TEs）状态改变与神经退行性疾病存在关联。然而，目前关于活体人类及创伤后状态下微量元素的相关研究数据仍较为匮乏。部分微量元素（铜——Cu、硒——Se、锌——Zn）参与机体必需的抗氧化防御机制。本研究旨在探究重型创伤性脑损伤（severe traumatic brain injury, TBI）患者脑内与血清中微量元素浓度随时间的变化趋势。
方法
本研究纳入20名成年重型TBI患者，于重症监护病房（intensive care unit, ICU）收治后3天内，通过脑微透析（cerebral microdialysis, CMD）技术及血液采样对其进行监测。采用电感耦合等离子体质谱（inductively coupled plasma mass spectrometry, ICP-MS）测定样本中的微量元素水平。
结果
本研究对脑间质液与血清中的铬（Cr）、铜（Cu）、钴（Co）、锰（Mn）、钼（Mo）、硒（Se）及锌（Zn）等微量元素浓度完成了定量分析。钴（Co）、钼（Mo）与锰（Mn）的血清水平与脑微透析检测值无显著统计学差异；铬（Cr）与锌（Zn）仅存在轻度差异；而铜（Cu）与硒（Se）的血清水平显著高于脑微透析检测值，约为其8~10倍。血清与脑内微量元素水平未发现显著相关性，仅钼（Mo）除外。
结论
本研究首次提供了活体重型TBI患者体内微量元素浓度的相关数据，其中脑内与血清微量元素浓度的最大差异见于铜（Cu）与硒（Se），可为急性脑损伤中微量元素动态变化的后续研究提供理论基础。