高压氧暴露对兔脑爆炸伤后脑组织水通道蛋白4的表达及血液灌注的影响

目的 通过研究高压氧(hyperaric oxygen,HBO)暴露对兔脑爆炸伤后脑组织水通道蛋白4(aquapodins-4,AQP-4)的表达及血液灌注的影响,探讨爆炸伤后脑水肿的形成机制.方法 150只新西兰大白兔采用数字表法随机分为对照组、高压氧治疗组(HBO组)和非治疗组.HBO组与非治疗组用纸雷管爆炸制作兔脑爆炸伤模型,随后分别随机分为伤后1h、6h、12h、24 h、72 h、7d、14d7个亚组,每亚组10只,对照组10只.采用RT-PCR法测定兔脑组织中AQP-4 mRNA的表达,磁共振灌注成像(perfusion weighted imaging,PWI)检测伤后不同时间点伤后脑组织血液灌注情况.结果 AQP-4 mRNA在伤后1h表达开始上调,3d达峰值,7d后缓慢下调.经HBO早期治疗,在6h后各时间点AQP-4mRNA表达均明显下调(P＜0.05).如伤后6h,非治疗组AQP-4 mRNA相对量为0.518±0.088,HBO组为0.327±0.027.经PWI检测,非治疗组伤后早期灌注明显下降,12h后灌注逐渐上升,并保持一定灌注量(接近对照组)持续2周;伤后早期(1～6 h)治疗组灌注下降更为明显.结论 HBO早期治疗可有效提高兔爆炸伤后脑组织血氧分压,增加血氧含量,缓解脑组织缺氧引起的继发性脑水肿.     

实验性兔颅脑爆炸伤后高压氧治疗作用的磁共振波谱研究

目的利用磁共振波谱技术(MRS)探讨高压氧治疗对颅脑爆炸伤时脑局部代谢变化的影响。方法新西兰大白兔100只随机分成对照组、创伤组和高压氧治疗组。采用600 mg TNT当量纸雷管在兔脑上方6.5 cm垂直距离爆炸以建立颅脑爆炸伤模型。对照组无损伤,创伤组爆炸伤后不进行任何治疗,高压氧治疗组于伤后行高压氧治疗。观察爆炸伤后各组兔的生理改变,采用MRS计算并分析各组不同时相点乙酰天门冬氨酸(NAA)/肌酸(Cr)、胆碱(Cho)/Cr的比值,分析比较各组脑组织含水量的变化。结果成功复制兔颅脑爆炸伤模型。与对照组相比,创伤组兔NAA/Cr比值伤后24 h明显下降(P<0.05),7 d后有所回升,14 d后再次下降(P<0.05);高压氧治疗组NAA/Cr比值下降较创伤组延迟,且幅度小。创伤组Cho/Cr比值伤后12 h明显升高,24 h下降,伤后3~14 d逐渐升高;高压氧治疗组Cho/Cr比值较创伤组升高,但7 d后无统计学差异。与对照组比较,创伤组、高压氧治疗组损伤或治疗1 h～7 d后脑组织含水量均明显升高(均P<0.05)。结论高压氧可改善局部神经元代谢,抑制脑水肿,增强局部胶质细胞增生修复。伤后7 d内...     

大鼠颅脑爆震伤模型的建立

目的建立稳定、可靠的大鼠颅脑爆震伤模型。方法 SD大鼠96只随机分为8、10、12cm组和对照组(n=24),将大鼠麻醉后分别放置距电雷管(600mgTNT当量)垂直距离8 cm、10 cm、12 cm处进行爆炸,于伤后24h行头颅MRI检查,6h、24h、3d、7d行检测损伤区光、电镜下病理变化。结果 8 cm组大鼠几乎在当天全部死亡,10 cm组大鼠存活时间也较短,少有存活7天,12 cm组大鼠存活时间在7天以上,且伤后24小时MRI提示挫伤区存在血肿及挫裂伤,病理学提示皮质、脑膜、脑室周围、神经元胞体、线粒体等均出现不同程度水肿。结论 600mgTNT电雷管在距离大鼠头部垂直12 cm处可制作稳定的大鼠颅脑爆震伤模型。     

利用血液回收机术中自体输血

为了节约血源,减少输血并发症,笔者对大手术中出血>500ml(不含心脏体外循环)的患者使用血液回收机施行自体输血,报告如下. 1 材料与方法 1.1 临床资料 1999年11月～2000年6月入本院手术患者24名.男性21例,女性3例.年龄21～7     

麻醉前应用盐酸戊乙奎醚对心率和血压的影响

盐酸戊乙奎醚(penehyclidine hydrochloride,长托宁)目前在麻醉前应用的报道甚少.本文以氢溴酸东莨菪碱(以下简称东莨菪碱)作比对,观察麻醉前肌注长托宁后患者心率和血压的变化.     

梅毒与HIV混合感染研究进展

近年来,梅毒与HIV混合感染的发病率在全世界范围内日益增多.既感染了梅毒螺旋体又感染了HIV的患者,因机体免疫力下降可使梅毒的自然病程、梅毒血清反应及治疗反应发生变化.此文就HIV阳性人群中梅毒的流行病学、临床特征、诊断、治疗及随访的一些关键问题作了综述.     

颅脑爆震伤后兔脑内代谢变化的磁共振波谱研究

目的 利用磁共振波谱技术探讨颅脑爆震伤后不同时间段脑局部代谢变化.方法 新西兰大白兔45只采用随机数字表法分为对照组(10只)和创伤组(35只),采用600 mgTNT当量纸雷管在创伤组兔脑上方约6.5 cm垂直距离爆炸,于伤后1,6,12,24 h、3,7,14 d用磁共振波谱技术观测动物存活情况,并检测脑损伤区病理及磁共振波谱表现,观察乙酰天门冬氨酸(N-acetylaspartate,NAA)/肌酸(creatine,Cr)、胆碱(choline,Cho)/Cr在爆震伤后随时间发展的演变过程.结果 创伤组兔存活时间在7 d以上,病理及常规MRI示脑挫伤病灶;NAA/Cr均值在损伤后1 h明显下降,持续至伤后24 h,24 h后义上升,7 d后再次下降.Cho/Cr均值在损伤1 h后即明显升高,12 h后下降,3 d后义逐渐升高.结论 磁共振波谱技术可反映兔颅脑爆炸伤不同时间段局部组织的代谢变化,为了解爆雀伤后局部组织变化情况及判断组织损伤类型提供理论依据.

Abstract：

Objective To evaluate the regional cerebral metabolic changes in different episodes by magnetic resonance spectroscopy (MRS) after explosive brain injury in rabbits. Methods Fortyfive New Zealand white rabbits were randomly divided into eight groups, ie, normal control group( 10 rabbits) and trauma group (35 rabbits). The explosive injury in trauma group was induced by explosion of 600 mg TNT equivalent of paper detonators at 6.5 cm above the rabbit brain. The rabbits in trauma group was divided into 1,6, 12, 24 hours, 3, 7, 14 days subgroups (6 rabbits per group). The survival rate was observed at different time points after explosive injury. The MRS was used to detect the regional cerebral metabolic changes including N-acetylaspartate (NAA)/creatine (Cr) ratio and choline(Cho)/Cr ratio as well as evolution of blast injuries over time. Results The rabbits survived for overseven days in the trauma groups, with typical brain contusion manifested by pathological and conventional MRI. Compared with the normal control group, the NAA/Cr ratio was markedly decreased at one hour after injury, slightly rose again at 24 hours and fell again after seven days. The Cho/Cr ratio was markedly increased at one hour after injury, slightly fell again at 12 hours and rose again at three days after injury.Conclusions MRS can manifest the regional cerebral metabolic changes of rabbits with explosive injury at different time points and hence provide a theoretical basis for understanding the local tissue changes and determining the type of tissue damage after blast injury.     

兔颅脑爆炸伤后水通道蛋白-4表达与高压氧治疗作用

目的研究兔颅脑爆炸伤后水通道蛋白4(AQP-4)的表达及高压氧早期治疗的影响。方法将新西兰大白兔150只,随机分为对照组、治疗组和非治疗组;其中对照组10只,另两组各70只。非治疗组和治疗组均采用纸雷管爆炸制作兔颅脑爆炸伤模型,并对治疗组采用早期高压氧治疗。三组均采用干湿法测定脑组织含水量,Western Blot法测定AQP-4表达情况。结果非治疗组与治疗组脑组织含水量和AQP-4在伤后1 h开始升高,72 h达高峰,7 d后逐渐下降。在伤后6 h后各时间点,治疗组AQP-4的表达均较非治疗组明显下调(P<0.05)。非治疗组脑组织含水量与AQP-4表达变化呈正相关(r=0.876 7,P<0.01)。结论兔颅脑爆炸伤后AQP-4表达可能与脑组织缺氧有关,而高压氧早期治疗可缓解脑组织缺氧引起的继发性脑水肿。     

MRS联合DWI观察实验性兔颅脑爆震伤后高压氧的治疗作用

目的 利用磁共振波谱技术及磁共振弥散加权成像探讨高压氧治疗颅脑爆震伤不同时间段脑局部代谢及水分子运动的变化.方法 90只新西兰大白兔按随机数字表法分成对照组、创伤组和高压氧治疗组,后2组采用600 mg TNT当量纸雷管在兔脑上方6.5 cm垂直距离爆炸制作颅脑爆震伤模型,高压氧治疗组待生命体征稳定后即给予不同疗程的高压氧治疗.于模型制作后1 d、3 d、7 d、14d、21 d等时间点观察兔存活情况,磁共振波谱观察乙酰天门冬氨酸(NAA)/肌酸(Cr)、NAA/胆碱(Cho)+Cr随时间发展的演变过程,磁共振弥散加权成像观察表观弥散系数(ADC)值随时间发展的演变过程.结果 创伤组NAA/Cr均值在损伤后明显下降,7 d后有所回升,高压氧治疗组NAA/Cr均值较创伤组高,比较差异有统计学意义(P＜0.05).创伤组NAA/Cho+Cr均值在损伤后即明显降低,高压氧治疗组NAA/Cho+Cr均值较创伤组高,比较差异有统计学意义(P＜0.05).创伤组兴趣区ADC值在1 d时明显下降,3 d后逐渐上升,高压氧治疗组ADC值均较创伤组高,比较差异有统计学意义(P＜0.05).结论 高压氧可通过改善局部神经元代谢、抑制脑水肿、增强局部胶质增生修复等改善颅脑爆震伤的预后,伤后早期干预可能更有利.

Abstract：

Objective To evaluate the role of magnetic resonance spectroscopy (MRS) and diffusion-weighted MRI (DWI) in detecting regional cerebral metabolic changes and changes of water molecular motion in rabbits after explosive brain injury at different time points of injury after being treated with hyperbaric oxygen therapy. Methods Ninety New Zealand white rabbits were divided into control group, trauma group and hyperbaric oxygen treatment group. The injured models in the later 2 groups were established using 600 mg TNT equivalent of paper detonators in the rabbit brain at the top of 6.5 cm vertical distance. Rabbits in the trauma group and hyperbaric oxygen treatment group were sub-divided into 1, 3, 7, 14 and 21 d treatment groups, respectively. The survival of these rabbits was observed at these time points. Hyperbaric oxygen treatments lasting for 1, 3, 7, 14 and 21 d were given to each hyperbaric oxygen treatment sub-groups, respectively. Performance under MRS was detected and dynamic changes of N-acetylaspartate (NAA)/creatine (Cr) ratio and NAA/choline(Cho)+Cr value were observed with MRS. DWI was employed to detect the dynamic changes of apparent diffusion coefficient (ADC) values. Results The NAA/Cr ratio in the trauma group markedly decreased right after the injury and slightly rose 7 d after the injury. Compared with that in the trauma group, the NAA/Cr ratio in the hyperbaric oxygen treatment group was significantly increased (P＜0.05). The NAA/Cho+Cr value in the trauma group was markedly decreased right after the injury, while that in the hyperbaric oxygen treatment group was obviously increased as compared with that in the trauma group (P＜0.05). ADC values in the region of interest of the trauma group was decreased after 1 d of treatment and gradually increased after 3 d of treatment; the ADC values in the hyperbaric oxygen treatment group was obviously higher than those in the trauma group (P＜0.05). Conclusion Hyperbaric oxygen might improve the prognosis by improving local metabolism of neurons, inhibiting brain edema, and enhancing local gliosis repair;, ultra-early intervention (within one week of injury) may be much favorable for animals/patients after explosive brain injury.