亚低温对颅脑损伤后脑血管内皮细胞紧密连接开放的影响

目的　观察颅脑损伤后早期亚低温治疗对脑毛细血管内皮细胞紧密连接开放的影响 ,阐明亚低温降低伤后血脑屏障通透性的可能机制。　方法　Wistar大鼠 90只 ,随机分为常温对照组 (10只 )、常温损伤组 (40只 )和亚低温治疗组 (40只 )。在镧示踪法电镜下分别观察亚低温及常温条件下颅脑损伤后内皮细胞紧密连接的开放及其程度 ;用干 -湿重法测定常温损伤组及亚低温治疗组伤后不同时相脑组织含水量并行统计学分析。　结果　常温损伤组伤后 3h紧密连接初步开放 ,2 4～ 4 8h紧密连接开放达高峰 ,72h紧密连接仍大量开放。亚低温治疗组紧密连接仅轻度开放 ;亚低温治疗组脑组织含水量较常温损伤组明显减少 ,伤后 3,2 4 ,72h差异有显著性意义(P <0 .0 5 ) ,伤后 4 8h差异有非常显著性意义 (P <0 .0 1)。　结论　亚低温有减轻颅脑损伤后血脑屏障毛细血管内皮细胞紧密连接的开放程度及减轻脑水肿的作用 ,亚低温减轻伤后内皮细胞紧密连接开放是降低伤后血脑屏障通透性机制之一。     

伤灶局部亚低温及伤灶局部引流治疗大鼠创伤性脑损伤

目的观察伤灶局部引流及伤灶局部亚低温联合治疗对SD大鼠创伤性脑损伤后脑水含量、Na 含量、血脑屏障的变化,探讨其对创伤性脑损伤的治疗作用及可能机制。方法实验动物随机分成5组:S组为假手术组;M组为脑外伤模型组;LH组为伤灶局部亚低温治疗组;LD组为伤灶局部引流组;LDH组为伤灶局部引流 伤灶局部亚低温联合治疗组。采用干湿重法测伤灶脑组织含水量,原子吸收火焰分光光度法测Na 含量,伊文思蓝检测血脑屏障开放情况。结果(1)脑组织水含量:LH、LD、LDH组伤灶区脑组织含水量分别低于M组(P<0.05);LDH组脑组织水含量低于LD组和LH组(P<0.05)。(2)钠含量:钠离子变化与含水量变化一致,LH组、LD组、LDH组伤灶区脑组织钠离子含量分别低于M组(P<0.05);LDH组钠含量低于LD组和LH组(P<0.05)。(3)EB含量:LH组、LD组、LDH组伤灶区脑组织EB含量分别低于M组(P<0.05);LDH组EB含量低于LD组和LH组(P<0.05)。(4)LD、LDH组引流量分别为(0.2308±0.0356)g、(0.3456±0.0692)g。结论伤灶局部亚低温、伤灶局部引流或二者联合治疗均对创伤性脑损伤有治疗作用,但联合治疗效果优于单独治疗。其治疗效果可能与直接引流出水肿液、减轻脑水肿,促进被破坏血脑屏障的早期修复等有关。     

亚低温对颅脑损伤后脑细胞内钙离子浓度及脑水肿影响的实验研究

目的　研究大鼠颅脑损伤后亚低温治疗对脑细胞内钙离子浓度的影响 ,揭示亚低温保护脑细胞钙离子通道及减轻脑水肿的作用。方法　通过硬膜外自由落体打击法 ,制备颅脑损伤动物模型 ;采用激光扫描共聚焦显微镜技术 ,测定颅脑损伤后脑细胞内钙离子浓度变化及脑组织含水量的变化。结果　亚低温组大鼠伤后 6、2 4、4 8小时脑细胞内钙离子浓度明显低于同时相常温组大鼠 (P <0 .0 1) ,伤后 4 8小时亚低温组脑水肿程度较轻 (P <0 .0 5 )。结论　亚低温能够减少颅脑外伤后大量胞外钙离子移入胞内 ,减缓脑细胞内钙超载 ,减轻脑水肿程度     

脑创伤大鼠透析液一氧化氮变化及亚低温治疗的影响

目的　研究脑创伤大鼠致伤后致伤中心、致伤区外侧侧脑室和致伤对侧海马区透析液一氧化氮 (NO)的变化以及亚低温治疗的影响。　方法　选用Wistar大鼠制作大鼠脑创伤模型 ;随机分为正常对照组、常温致伤组和亚低温治疗组 ;透析管插入致伤区中心、致伤区外侧侧脑室和致伤对侧海马区 ,灌流速度为 4 μl min ,透析 5h。亚低温治疗组在脑创伤后用冰袋全身降温至脑温30℃保持 1h ,然后加热复温至 37℃。　结果　 (1)正常对照组致伤区中心、致伤区外侧侧脑室和致伤对侧海马区的NO分别为 (14 .17± 2 .0 3)、(2 5 .4 3± 1.2 7)、(17.10± 1.83) μmol L ;(2 )致伤区中心NO :常温致伤组明显升高 (P <0 .0 5 ) ,伤后 0 .5h最高 ;亚低温治疗组伤后 1hNO较正常对照组明显升高 ,0 .5h明显低于常温致伤组 ;(3)致伤区外侧NO :常温致伤组伤后与正常对照组无区别 ;亚低温治疗组NO较两组明显降低 ,复温后逐渐恢复 ,但仍明显比常温致伤组低 ;(4)对侧海马区NO :常温致伤组和亚低温治疗组NO均下降 ,但两组之间差异无显著性意义。　结论　亚低温治疗对脑创伤后早期致伤区中心组织NO有一定的抑制作用 ,对致伤对侧海马区NO无影响 ,主要是明显降低了致伤区外侧正常脑组织细胞外液NO的水平 ,具有保护脑创伤后正常组织的作用 ,从而     

颅脑外伤后亚低温治疗对Calpain表达的影响

目的 探讨亚低温治疗对颅脑外伤后Calpain基因和蛋白表达的影响.方法 将27只SD大鼠按随机数字表法分为正常对照组、常温脑损伤组和亚低温脑损伤组.脑损伤组分别接受右顶部侧方中度液压损伤打击,其中亚低温组在伤后即刻接受持续4 h的亚低温治疗[肛温(32±0.5)℃].在伤后6,12,24和72 h四个时间点分别通过荧光PCR、Western blot定量检测各组打击伤灶周围皮层钙蛋白酶Calpain基因转录和蛋白分子表达的水平,同时运用免疫荧光观察Calpain蛋白分布情况.结果 与常温组比较,亚低温使颅脑外伤后12 h及24 h Calpain基因的转录较正常对照和同时间点常温脑损伤组显著增加(P<0.05).然而,伤后6,12,24和72 h亚低温治疗均使Calpain在蛋白水平较同时间点常温脑损伤组表达升高的程度显著抑制(P<0.05).结论颅脑外伤后亚低温治疗的脑保护机制可能与其在Calpain基因转录后明显抑制Calpain蛋白水平的表达有关.     

高温、亚低温对大鼠重型脑损伤血脑屏障通透性的影响及其机制

目的 观察高温、亚低温对重型脑损伤大鼠血脑屏障(blood-brain barrier,BBB)通透性及脑组织基质金属蛋白酶-9(MMP-9)活性和层黏连蛋白表达的影响,探讨高温、亚低温改变血脑屏障通透性的作用机制.方法 72只SD大鼠随机分为假手术组、脑损伤组、脑损伤后高温组和亚低温组,检测伤灶区脑组织伊文思蓝(EB)含量、MMP-9活性和层黏连蛋白表达.结果 脑损伤后高温组EB含量、MMP-9活性高于脑损伤组(P<0.05),而层黏连蛋白含量低于脑损伤组(P<0.05).亚低温组EB含量、MMP-9活性低于脑损伤组(P<0.05),而层黏连蛋白含量高于脑损伤组(P<0.05).结论 脑损伤后MMP-9活性增高,降解层黏连蛋白,导致血脑屏障通透性增加.脑损伤后高温增加血脑屏障通透性,亚低温治疗降低血脑屏障通透性,其作用可能与二者改变MMP-9活性有关.     

弥漫性脑创伤与二次脑损伤发生机制研究

为研究弥漫性脑创伤 (DBI)与二次脑损伤 (SBI)后鼠脑代谢型谷氨酸受体 1a(mGluR1a)、cAMP、cGMP含量变化及I类mGluRs拮抗剂MCPG的治疗作用 ,将大鼠随机分为假手术对照、单纯DBI、脑损伤合并SBI及MCPG作用组。脑损伤后 ,以低血压作为SBI指标 ,于伤后不同时间进行免疫组化和放射免疫研究。结果发现 ,与对照组比较 ,单纯DBI组脑皮层mGluR1a阳性神经元表达在伤后 1h增加 ,2 4h达高峰 (P <0 .0 1) ,伤后2 4hcAMP水平下降 ,cGMP升高 ,cAMP/cGMP比值下降 ;合并SBI组 ,mGluR1a阳性神经元表达在伤后 0 5h即明显增加 ,6h达高峰 (P <0 0 1) ,cAMP改变也更加明显 ;MCPG可减少SBI后损伤神经元的数目。提示mGluR1a参与了细胞兴奋性毒性和代谢应急 ,是加重脑损害的关键因素。     

亚低温治疗对重型脑创伤脑组织糖代谢及甘油的影响

目的研究亚低温对重型脑创伤患者脑组织糖代谢及甘油的影响. 方法 33例患者随机分为亚低温组和常温组,将微透析探针分别置入病损周边区、病灶对侧的相应位置及腹部皮下脂肪组织,分析亚低温组及常温组脑细胞间液(extracellular fluid, ECF)的乳酸/丙酮酸 (lactate/pyruvate,L/P)、乳酸/葡萄糖(lactate/glucose,L/G)及甘油(glycerol,Gly)浓度. 结果亚低温组比常温组““““正常区““““脑 ECF的L/P有明显降低;亚低温组比常温组病损周边区甘油、L/G及L/P有明显降低;常温组病损周边区比““““正常区““““的甘油、L/G及L/P明显增高;亚低温组病损周边区L/P比““““正常区““““ 有明显增高. 结论亚低温治疗可能通过降低病损周边区脑ECF中L/P、L/G及甘油的浓度及““““正常区““““ L/P的浓度而发挥脑保护作用;颅脑创伤后病损周边区更易发生能量代谢紊乱及细胞膜降解,亚低温对这一区域有显著保护作用.     

亚低温对创伤性脑损伤后线粒体呼吸功能和超微结构的影响

目的 研究亚低温治疗对创伤性脑损伤(TBI)大鼠线粒体超微结构和呼吸功能的影响.方法 利用液压打击(FPI)制作中度TBI大鼠模型,并随机分为假手术对照组、常温TBI组(肛温36～37℃)、亚低温TBI组(肛温31～33℃,低温持续2 h).各组于脑外伤后2,24 h、3 d和7 d断头取脑,取伤侧海马组织固定,透射电镜观察线粒体形态改变.差速离心法提取伤侧大脑线粒体,采用Clark氧电极法测定线粒体的氧呼吸速率,计算呼吸控制比(RCR)值和磷氧比值(P/O).结果 (1)电镜下常温TBI组线粒体结构形态损伤程度较重,亚低温TBI组线粒体形态基本完好;(2)线粒体RCR值和P/O值在TBI后2 h就显著下降,以24 h为最低(P＜0.01),在7 d时RCR仍然显著低于假手术对照组,P/O值恢复正常.亚低温TBI组线粒体RCR值变化趋势同常温TBI组,但在3 d内RCR值均显著高于常温TBI组,P/O值在3 d后恢复正常.结论 TBI后,线粒体的呼吸功能明显下降,亚低温可以明显改善线粒体的呼吸功能,保护线粒体结构完整性.     

急性缺氧对脑损伤大鼠脑皮层代谢型谷氨酸受体1α表达的影响

目的　观察急性中度缺氧对脑损伤大鼠脑皮层代谢型谷氨酸受体 1α (metabotropicglutam ate receptor 1α,m Glu R1α)表达的影响 ,探讨缺氧诱导二次脑损伤的致伤机理。　方法　 90只雄性 SD大鼠随机分为对照组 ,损伤组 (改良 Marm arou脑损伤模型 )、缺氧 (4 0 0 0 m高度 ) 10 min组、缺氧 30 m in组、损伤后缺氧 10 min组、损伤后缺氧 30 min组等 6组 ,各组在相应处理后 4h取标本 ,行免疫组化、HE染色及电镜检测。光镜下计数每高倍视野中损伤神经元及 m Glu R1α阳性神经元的数目 ,并对实验结果进行析因设计的方差分析。　结果　 10 m in和 30 min缺氧对正常鼠脑皮层的显微、超微结构及 m Glu R1α表达无明显影响 (P>0 .0 5 ) ;10 m in缺氧也未导致脑损伤大鼠脑皮层显微、超微结构及 m Glu R1α表达明显改变 (P>0 .0 5 ) ;而 30 min缺氧可诱导脑损伤大鼠脑皮层显微及超微结构明显改变 ,m Glu R1α表达明显增高 (P<0 .0 1)。　结论　 30 min急性中度缺氧可加剧脑损伤大鼠脑皮层神经元损伤 ,同时诱导 m Glu R1α高表达 ,提示 m Glu R1α可能参与了缺氧诱导的二次脑损伤过程     

Knee injury and Osteoarthritis Outcome Score (KOOS) - validation of a Swedish version

The Knee injury and Osteoarthritis Outcome Score (KOOS) is a self-administered instrument measuring outcome after knee injury at impairment, disability, and handicap level in five subscales. Reliability, validity, and responsiveness of a Swedish version was assessed in 142 patients who underwent arthroscopy because of injury to the menisci, anterior cruciate ligament, or cartilage of the knee. The clinimetric properties were found to be good and comparable to the American version of the KOOS. Comparison to the Short Form-36 and the Lysholm knee scoring scale revealed expected correlations and construct validity. Item by item, symptoms and functional limitations were compared between diagnostic groups. High responsiveness was found three months after arthroscopic partial meniscectomy for all subscales but Activities of Daily Living.     

Endovascular management of carotid-cavernous fistulas

Objective To investigate endovascular treatment of traumatic direct carotid-cavernous fistulas （CCF） and their complications such as pseudoaneurysms. Methods： Over a five-year period, 22 patients with traumatic direct CCFs were treated endovascularly in our institution. Thirteen patients were treated once with the result of CCF occluded, 8 twice and 1 three times. Treatment modalities included balloon occlusion of the CCF, sacrifice of the ipsilateral internal carotid artery with detachable balloon, coll embolization of the cavernous sinus and secondary pseudoaneurysms, and covered-stem management of the pseudoaneurysms. Results All the direct CCFs were successfully managed endovascularly. Four patients developed a pseudoaneurysm after the occlusion of the CCF with an incidence of pseudoaneurysm formation of 18.2% （4/22）. A total number of 8 patients experienced permanent occlusion of the ICA with a rate of ICA occlusion reaching 36.4% （8/22）. Followed up through telephone consultation from 6 months to 5 years, all did well with no recurrence of CCF symptoms and signs. Conclusion Traumatic direct CCFs can be successfully managed with endovascular means. The pseudoaneurysms secondary to the occlusion of the CCFs can be occluded with stent-assisted coiling and implantation of covered stents.     

The role of interventional radiology in trauma

Introduction Interventional Radiology has evolved into a specialty having enormous input into the care of the traumatized patient.In all hospitals,regardless of size,the Interventional Radiologist must consider their relationships with the trauma service in order to     

The acutely limping child

Acute limping may be the result of multiple pathologies in children. The differential diagnosis varies based on the age of the child. Irrespective of age, the initial imaging work-up includes AP and frog leg radiographs of the pelvis and ultrasound; MRI may sometimes be helpful. In children less than 3 years, infections and trauma are most frequent. MRI is the imaging modality of choice when osteomyelitis is clinically suspected. Between the ages of 3 and 10 years, transient synovitis of the hip and Legg-Calvé-Perthes disease are main considerations but infection, inflammation and focal bony lesions are also considered. In children over 10 years, slipped capital femoral epiphysis also is considered.     

Diagnóstico ecográfico del neumotórax

The ultrasonographic diagnosis of pneumothorax is based on the analysis of artifacts. It is possible to confirm or rule out pneumothorax by combining the following signs: lung sliding, the A and B lines, and the lung point. One fundamental advantage of lung ultrasonography is its easy access in any critical situation, especially in patients in the intensive care unit. For this reason, chest ultrasonography can be used as an alternative to plain-film X-rays and computed tomography in critical patients and in patients with normal plain films in whom pneumothorax is strongly suspected, as well as to evaluate the extent of the pneumothorax and monitor its evolution.     

Carbohydrate Supplementation during Exercise: Does It Help? How Much is Too Much?

KEY POINTS· Carbohydrate intake during exercise can delay the onset of fatigue and improve performance of prolonged exercise as well as exercise of shorter duration and greater intensity (e.g., continuous exercise lasting about 1h and intermittent high-intensity exercise), but the mechanisms by which performance is improved are different.