CAJ | 학술논문

目的根据弥漫性轴索损伤(DAI)临床实际力学发生机制,在联合损伤模型基础上探讨直线加速和旋转加速的联合损伤效应. 方法 116只SD大鼠采用随机数字表法分为正常对照组(8只)、单纯损伤组(72只){包括单纯打击直线加速损伤组(36只,大鼠接受450 g钢砝码于0.9m高处坠落打击后直线加速1 cm)和单纯旋转加速损伤组[36只,大鼠发生最大角加速度为(133±15) krad/s2的90°旋转]}及联合损伤组(36只,大鼠接受上述打击直线和旋转加速的复合损伤过程).观察大鼠伤后存活情况、角膜反射消失时间及组织病理学改变. 结果 (1)各损伤组大鼠均出现角膜反射消失时间的延长及肢体活动减少等行为学抑制表现,但联合损伤组较单纯损伤组明显.大鼠死亡仅限于联合损伤组,死亡率达20.8％.(2)各损伤组大鼠大体及HE染色均见蛛网膜下腔或脑室出血及脑组织结构疏松水肿等病理学改变,但脑白质撕裂性出血及HE染色轴索损伤征象仅见于联合损伤组;β-聚磷酸铵免疫组化染色及电镜仅观察到联合损伤组大鼠存在轴索损伤. 结论单一直线加速或旋转加速在低水平力学参数下难以产生DAI,但两者联合可产生协同和非线性效应而使两种力学在较低水平情况下复制出中、重型DAI.
목적 근거미만성축색손상(DAI)림상실제역학발생궤제,재연합손상모형기출상탐토직선가속화선전가속적연합손상효응. 방법 116지SD대서채용수궤수자표법분위정상대조조(8지)、단순손상조(72지){포괄단순타격직선가속손상조(36지,대서접수450 g강겁마우0.9m고처추락타격후직선가속1 cm)화단순선전가속손상조[36지,대서발생최대각가속도위(133±15) krad/s2적90°선전]}급연합손상조(36지,대서접수상술타격직선화선전가속적복합손상과정).관찰대서상후존활정황、각막반사소실시간급조직병이학개변. 결과 (1)각손상조대서균출현각막반사소실시간적연장급지체활동감소등행위학억제표현,단연합손상조교단순손상조명현.대서사망부한우연합손상조,사망솔체20.8％.(2)각손상조대서대체급HE염색균견주망막하강혹뇌실출혈급뇌조직결구소송수종등병이학개변,단뇌백질시렬성출혈급HE염색축색손상정상부견우연합손상조;β-취린산안면역조화염색급전경부관찰도연합손상조대서존재축색손상. 결론 단일직선가속혹선전가속재저수평역학삼수하난이산생DAI,단량자연합가산생협동화비선성효응이사량충역학재교저수평정황하복제출중、중형DAI.
Objective To investigate the combined injury effect of impact linear acceleration and angular acceleration by exploring the combined injury mechanism of diffuse axonal injury (DAI).Methods According to the mechanism ofDAI,a new experimental facility was designed.This model let the rats instantly rotate 90 degree after being experienced impact injury and linear acceleration.Group 1 animals,a 450 g weight was dropped from a height of 0.9 m with no subsequent rotation (n=36); group 2 animals underwent purely angular acceleration with no preceding impact-acceleration injury (n=36); group 3 animals were subjected to the combined linear and angular accelerations (n=36); group 4 animals served as the controls (n=8).Pathologic and behavioral examinations were conducted to verify characteristics of DAI.Results (1) Group 3 animals took significantly longer time to regain corneal reflex (12.1 ±3.4 min) and had decreased limb exercise as compared with other groups (P＜0.05).Besides,mortality was only observed in Group 3,reaching 20.8％.(2) Macroscopic damage was observed in all brain-injured animals.However,axonal damage and hemorrhagic tissue tears were only noted in Group 3.Both β-APP immunohistochemistry and electron microscopy indicated axonal injury only in Group 3.Conclusions The combination of impact linear and angular accelerations can cause non-linear and synergistic effects to produce severe DAI with mild levels of both forms of acceleration.