猴脑选择性超深低温断血流的影像和病理研究

目的探讨猴脑选择性超深低温断血流复苏前后的影像和病理变化。方法4~10岁健康恒河猴10只,随机分为三组:四血管(双侧颈总动脉及椎动脉)阻断冷灌注组,两血管(双侧颈总动脉)阻断等温灌注组,两血管阻断冷灌注组。常温下临时阻断双侧颈部血管后,通过一侧颈内动脉冷灌注,同侧颈内静脉回流,阻断其它颈部血管,建立选择性脑局部体外循环通路,降低脑温至(15.1±0.9)℃,60min恢复脑血流,实验动物自然复苏.于手术前,恢复脑血流后4h、24h、72h、21d分别行常规MRI(扫描序列包括T1WI、T2WI)弥散加权成像(diffuseweightedimagine,DWI)MRI,手术中持续监测生命体征及血流动力学指标变化,术后每周行神经功能缺失评分,脑组织及主要脏器行光镜观察。结果在10只实验猴中,两血管阻断冷灌注组4只恒河猴术中、术后血流动力学稳定,灌注60min后安全复苏并长期存活,术后头颅常规MRI和DWI检查未见异常,术后神经功能评分无异常,主要器官组织形态未见异常;两血管阻断等温灌注组2只及四血管阻断冷灌注组4只于灌注60min后均未能安全复苏,术后24h内死亡,四血管组1例术后存活超过6h,行DWI发现右基底节区有梗塞灶;余术后全部死亡,主要器官组织形态可见不同程度异常。结论猴脑在选择性超深低温状态下,阻断双侧颈总动脉血流60min后可安全复苏,阻断血流及复苏对血流动力学、脑组织形态及神经功能无明显影响。     

细胞因子对猴脑选择性超深低温断血流复苏缺血性脑保护的影响机制

目的观察猴脑选择性超深低温断血流复苏实验前后血清中细胞因子的动态变化，了解脑缺血后选择性超深低温复苏对缺血性脑保护的炎性机制。方法健康恒河猴4只，先阻断双侧颈总动脉血流10min，然后建立闭胸式脑局部体外循环，行一侧颈内动脉冷灌注，同侧颈内静脉回流。60min后恢复脑血流，自然复苏。应用ELISA法统一测定实验前后猴血清中IL-2、IL-10、TNF-α、IFN-γ的浓度。结果4只恒河猴术后安全复苏并长期存活，术后头颅MRI检查正常，术后神经功能评分无异常。四种细胞因子在灌注结束后较术前均明显增高（P〈0．05），24h后恢复至术前水平，72h测得值与术前无显著差异（P〉0．05）。Spearman相关系数统计显示不同时间点促炎因子IL-2、TNF-α、IFN-γ与抑炎因子IL-10之间呈明显的正相关。结论猴脑选择性超深低温断血流复苏可引起抗炎细胞因子与促炎细胞因子一过性增高，其中抑炎因子IL-10的明显表达和促炎因子之间互相抑制，互相作用，促使细胞因子网络维持动态平衡，从而减轻机体炎性反应同时抑制了脑缺血后机体炎性反应所引起的脑组织损伤，发挥脑保护作用。     

选择性深低温血流阻断猴海马超微结构和波形蛋白表达的变化**

背景：前期研究显示,选择性深低温顺行脑灌注能提高猴脑对缺血缺氧的耐受性。 目的：观察选择性深低温血流阻断对猴海马超微结构和波形蛋白表达的影响。 方法：将8只健康成年恒河猴随机分为两组：深低温组(n=5)在常温下阻断猴双侧颈总动脉及颈内静脉10 min,然后通过一侧颈内动脉灌注4 ℃林格氏液,同侧颈内静脉回流,使脑温维持在18 ℃以下,60 min后恢复脑血流;常温组(n=3)除灌注液改为37 ℃林格氏液外,其余与深低温组相同。 结果与结论：深低温组猴全部成功复苏,海马组织形态及超微结构未见明显异常。常温组猴全部死亡,未能成功复苏,海马组织形态及超微结构有不同程度异常。与常温组比较,深低温组海马波形蛋白表达显著降低(P < 0.01)。说明阻断双侧颈总动脉10 min后行选择性深低温顺行脑灌注可下调海马波形蛋白表达,保护海马组织,减轻脑缺血损害。     

腺苷预处理对大鼠脑缺血-再灌注损伤后脑内肿瘤坏死因子α和核因子κB表达的影响

目的 通过观察腺苷预处理对脑缺血-再灌注（IR）损伤后大鼠脑内肿瘤坏死因子α（TNF-α）和核因子κB（NF-κB）表达的影响,探讨腺苷对大鼠脑缺血-再灌注损伤的保护机制。方法 Sprague-Dawley大鼠60只随机分为假手术组（F组）、缺血-再灌注组（IR组）和腺苷预处理缺血-再灌注组（AP组）,每组动物按照缺血-再灌注后2 h、6 h、24 h及48 h这4个时间点随机分组,每组5只。采用大脑中动脉阻塞（MCAO）法制备大鼠大脑中动脉闭塞模型。通过对以上3组脑缺血 再灌注48 h后的大鼠脑组织行头颅MRI、HE染色以及对以上60只大鼠进行神经功能缺损评分,通过免疫组织化学方法观察大鼠脑组织中TNF-α和NF-κB的平均积分吸光度值进一步验证腺苷预处理对大鼠脑缺血-再灌注损伤的脑保护作用,探讨腺苷对大鼠脑缺血-再灌注损伤的保护机制。结果 F组大鼠术后无神经功能缺损体征,AP组和IR组大鼠术后均出现明显神经功能缺损体征。AP组和IR组大鼠神经功能缺损评分显著高于F组,AP组大鼠神经功能缺损评分显著低于IR组,差异均具有统计学意义（P＜0.05）。F组大鼠术后MRI中T1WI、T2WI均未见明显异常,AP组和IR组大鼠脑梗死体积显著高于F组,AP组大鼠脑梗死体积显著低于IR组,差异均具有统计学意义（P＜0.05）。AP组和IR组术后大鼠脑组织中TNF-α和NF-κB的表达显著高于F组,AP组术后大鼠脑组织中TNF-α和NF-κB的表达显著低于IR组,差异均具有统计学意义（P＜0.05）。结论 腺苷预处理可通过减少大鼠缺血-再灌注损伤后脑内TNF-α和NF-κB的表达而减轻神经细胞损伤,达到其脑保护作用。     

猴脑选择性超深低温模型中超滤对血容量的影响

目的通过研究猴脑选择性超深低温断血流复苏模型超滤前、中、后红细胞压积、血红蛋白、血糖等的变化,说明超滤可保证超深低温灌注过程中模型的稳定性,有利于恒河猴复苏。方法健康成年恒河猴15只,建立脑选择性超深低温模型,分别于术前、血液稀释后转流中30min、超滤停机后5min取样测定血糖、红细胞压积、血浆总蛋白。采用SPSS12．0软件包分析,采用单因素方差分析结果,P〈0．05认为差异有显著性。结果超滤后血糖明显升高,红细胞压积和血红蛋白在血液稀释后下降明显,超滤后明显回升,血容量基本维持平衡。结论猴脑选择性超深低温模型中应用超滤方法维持灌注前后渗透压的平衡,减轻血液稀释,减轻组织水肿,有利于恒河猴断血流后的复苏。     

缺血后适应对大鼠脑缺血/再灌注损伤的影响

目的：探讨缺血后适应对大鼠脑缺血/再灌注损伤的影响。方法:应用线栓法制作大鼠脑缺血/再灌注损伤模型；21只雄性SD大鼠随机分为缺血/再灌注组、夹闭单侧颈总动脉后处理组和夹闭双侧颈总动脉后处理组，每组7只。再灌注48 h，测定脑梗死体积；拔栓后1 h及处死大鼠前进行神经功能测定；梗死即刻、梗死后10 min、术中1 h、拔栓后即刻、每次夹/松颈总动脉时、干预后30 min等15个时点监测脑血流。结果:夹闭单侧、双侧颈总动脉后处理组大鼠脑组织梗死体积与缺血/再灌注组相比明显减小，有显著差异；3组脑血流各个时点方差分析差异无显著，但是夹闭双侧颈总动脉后处理组干预30 min后脑血流百分比较缺血/再灌注组、夹闭单侧颈总动脉后处理组降低9％。手术后1 h 3组神经功能评分P<0.05，差异显著，夹闭单侧、双侧颈总动脉后处理组神经功能缺损均比缺血/再灌注组减轻。结论:缺血后适应能够明显减小梗塞体积，改善大鼠术后1h神经功能评分，可能与缺血后适应调节早期再灌注时血流动力学状态有关。     

血管介入法导入自体血栓建立猴局部脑缺血模型

目的：采用血管介入法导入自体血栓，建立猴局部脑缺血动物模型，为脑缺血的相关研究提供创伤小、应用前景大的基础研究平台。 方法： 以12只食蟹猴为实验对象，采用血管介入法从股动脉将微导管超选至大脑中动脉（MCA）M₁分枝，导入自体血栓堵塞MCA。 结果：栓塞后，数字影像血管造影系统下可见M1段以后的血管显影不良；1 h后，CT灌注成像均显示大脑局部血流量和血容量下降，血流平均通过时间延长；48 h后常规CT平扫可见典型的低密度陈旧性局部脑缺血病灶。栓塞后24 h内，取两只动物尸体解剖，大脑切片TTC染色，显示患侧MCA区脑梗病灶；其余动物清醒后，缺血对侧肢体均有不同程度的瘫痪，神经功能评分均＜60分。 结论： 用血管介入法导入自体血栓建立的猴局部脑缺血动物模型，插管和栓塞过程清晰、定位准确、创伤小、并发症少、结果与临床更相似，在脑缺血的相关研究中有着较好的应用前景。     

兔经股动脉插管自体血栓大脑中动脉栓塞模型

目的经股动脉途径行选择性颈内动脉插管建立兔大脑中动脉（MCA）血栓栓塞模型,并评价其技术可行性及模型的稳定性。方法新西兰大白兔30只,雌雄不限,平均兔龄14个月,体质量4.1kg。对照组10只,实验组20只。经股动脉途径行选择性颈内动脉数字减影血管造影（DSA）,实验组向颈内动脉内注射1~5枚血栓,对照组仅注射造影剂。行DSA,观察脑血管闭塞情况,用改良Bederson评分法评价神经功能缺损,CT灌注成像观察脑血流灌注,磁共振扩散加权成像（DWI）、2,3,5-三苯基氯化四氮唑（TTC）染色观察脑梗塞情况。结果实验组17只兔（85%）脑缺血模型建立成功,表现为手术侧MCA主干闭塞,神经功能缺损,MCA供血区血流灌注异常,DWI信号、TTC染色异常。3只脑缺血模型建立失败,其中2只为颈内动脉栓塞,1只闭塞的MCA再通。对照组影像学及病理学均无异常。两组CT灌注参数差异有显著统计学意义（P〈0.01）。结论经股动脉途径行选择性颈内动脉插管建立兔MCA血栓栓塞模型具有创伤小、易存活等优点。选择合适的血栓及熟悉兔颈内动脉系统解剖及变异能提高局灶性脑缺血模型的稳定性及可重复性。     

脑电图及头颅MRI在早期小儿脑性瘫痪中的作用

目的探讨脑电图及头颅MRI在小儿脑性瘫痪早期诊断及治疗中的应用价值.方法对60例早期诊断脑性瘫痪患儿行脑电图及头颅MRI检查,并在康复治疗症状好转后3～12月对患儿进行脑电图随访.结果脑电图异常率85%,主要表现为双侧不对称,广泛性慢波节律改变及痫样波发作.头颅MRI异常率98.3%,主要表现为脑萎缩、外周性脑积水、脑白质发育不良等改变.脑电图及MRI异常符合率为85%.经过综合性康复治疗,脑电图随访90.2%恢复正常,脑电图的改善与临床症状的改善之间存在显著性关联(p＜0.05).结论脑电图及头颅MRI的结合应用可为脑性瘫痪的早期诊断提供较好诊断依据,并有助于判断预后及指导康复治疗.     

体外循环深低温低流量灌注的脑电图变化

本实验通过脑电图观察体外循环深低温低流量灌注下的变化。动物实验分为两组,第一组经体外循环转流降温至肛温20℃后采用不同灌注流量以观察脑电图变化;第二组在两种低流量灌注下的不同时间观察脑电图变化。第一纽发现脑电图波幅在流量75ml/(kz·min)以下时变小,流量5ml/(Kg·min)时均为平坦波。第二组以25ml/(kg·mil)转流后脑电波恢复早,波幅活跃,而以5ml/(kg·min)转流与深低温停循环相似,临床上采用该方法行四联症纠治术,术前、术毕和1～3个月随访,效果良好,脑电图表现与对照组之间无差异。     

局部亚低温对大鼠局灶脑缺血再灌注后神经营养因子-3表达的影响

目的：观察病变侧缺血至再灌期亚低温(32～33 ℃)对局灶脑缺血再灌注后梗死体积和神经营养因子-3(neurotrophin-3,NT-3)表达的影响。方法：采用改良线栓法建立大鼠大脑中动脉缺血再灌注模型,随机分为假手术组、常温缺血组和亚低温缺血组,缺血30 min后应用负反馈控温半导体制冷块对大鼠病变侧给予亚低温治疗并持续至再灌期。处死大鼠前进行神经功能缺陷评分,氯化三苯四氮唑染色及计算机图像分析技术观察脑梗死体积,采用免疫组织化学方法检测NT-3表达,末端脱核苷酸转移酶介导的dUTP缺口标记技术观察神经细胞凋亡情况。结果：同常温缺血组相比,亚低温缺血组梗死体积明显减少,NT-3阳性细胞数量增加,凋亡的神经细胞明显减少(均P<0.05)。神经功能缺陷评分亚低温缺血组明显低于相应时间点常温缺血组(P<0.05或P<0.01)。结论：病变侧亚低温可通过增加脑缺血后NT-3的表达水平,抑制细胞凋亡而发挥脑保护作用。     

亚低温对构建脑梗死模型大鼠梗死区神经再生微环境的影响

BACKGROUND: Numerous studies have demonstrated that mild hypothermia has a better protective effect on neurons after cerebral infarction. OBJECTIVE:To investigate the effect of mild hypothermia on nerve regeneration microenvironment of infarcted area in rat models of cerebral infarction and analyze its possible effects on neural functional recovery after cerebral infarction. METHODS:Twenty out of 65 adult female Sprague-Dawley rats were randomly selected as the sham group. The remaining 45 rats were subjected to carotid artery ligation to establish rat models of cerebral infarction. Five rats were rejected because of modeling failure or death, the remaining 40 rats were randomly and evenly divided into cerebral infarction and mild hypothermia groups. The head temperature of rats in the cerebral infarction group was downregulated to (37±1) ℃ using a semiconductor refrigeration instrument. The rats were transferred to the room with the temperature of 25 ℃ after the operation. Brain hypothermia was also induced in rats from the mild hypothermia group. At 13.0-14.0 minutes after establishing rat models of cerebral ischemia, the head on the side of cerebral ischemia was tightly connected with the probe of the semiconductor refrigeration instrument. The refrigerator temperature was adjusted to 6-8 ℃, so as to make the temperature of brain tissue on the lesion side at 32.0-33.0 ℃ for 4 hours. RESULTS AND CONCLUSION:Compared with the cerebral infarction group, the BBB scores of rats in the mild hypothermia group were distinctly increased, and the volume of infarcted area decreased. At 1 day after modeling, the expression level of growth associated protein 43 mRNA in brain tissue of rats in the mild hypothermia group was close to that in the cerebral infarction group. At 2 weeks after modeling, the expression level of growth associated protein 43 mRNA in brain tissue of rats in the mild hypothermia group was significantly increased compared with that in the cerebral infarction group. These results suggest that mild hypothermia therapy can protect nerve cells against injury caused by cerebral infarction and promote the recovery of neurological function. Its underlying mechanism may be related to the up-regulation of the expression of growth associated protein 43 in ischemic penumbra.     

Rapamycin保护大鼠缺血性脑损伤和特定脑区神经新生有关

目的:探讨缺血前给予自噬诱导剂对脑缺血损伤的保护效应及可能机制。方法:双侧颈总动脉结扎建立全脑缺血模型,再灌注后24 h,评价动物神经行为功能,连续脑切片,采用Nissl染色定量检测皮层及海马CA1区细胞密度;通过免疫荧光技术检测Caspase-3阳性神经元,计数皮层及海马CA1凋亡细胞数量;激光共聚焦显微镜观察并计数海马齿状回颗粒下层内呈Ki67阳性、GFAP(胶质纤维酸性蛋白)阴性(Ki67+/GFAP-)细胞的数量。结果:Rapamycin术前预处理可以改善缺血导致的神经功能缺陷(P<0.05)。Nissl染色结果表明Ra-pamincy术前1 h给药可以减轻缺血导致的皮层(P<0.01)及海马CA1区(P<0.01)细胞丢失。同时,Rapamycin术前给药也显著减少了缺血导致的皮层及海马CA1区内Caspase-3阳性细胞的数量,组间比较有显著性差异(P<0.05)。Rapamycin术前1 h给药增加了海马齿状回内Ki67+/GFAP-细胞的数量,和缺血组比较差异有显著性(P<0.05)。结论:在全脑缺血模型上,通过自噬活化途径的缺血预处理可以保护缺血性脑损伤,这一作用和Rapamycin减少凋亡、增加新生神经细胞的数量有关。     

Two cases of asystolic cardiac arrests managed with therapeutic hypothermia

Poor neurological outcome is a common sequel of prolonged cardiac arrest. Although Therapeutic Hypothermia (TH) for neuroprotection has been a subject for research for over Half a century, its use has been limited because of many controversies and lack of clear guidelines. However for over two decades there has been a revival of interest in mild therapeutic hypothermia (32-34°C) for neuroprotection. However its use after primary asystolic cardiac arrest has been questioned.Herein presenting two cases of prolonged asystolic arrest (39 minutes and 25 minutes); where therapeutic hypothermia was successfully used in following prolonged cardio pulmonary resuscitation. On patients who were in deep coma after resuscitation, TH was applied for 24 hours as per institutional protocol with full neurological recovery in both the cases. Therapeutic hypothermia might have a potential role in even in non-shockable arrests and should be considered in every successful cardiopulmonary resuscitation with poor neurological status.     

A new method of inducing selective brain hypothermia with saline perfusion into the subdural space: effects on transient cerebral ischemia in cats

In this study, we tested brain surface cooling as a new method of inducing selective brain hypothermia, and evaluated its effects on focal cerebral ischemia using a cat model of transient middle cerebral artery (MCA) occlusion. Cats underwent 1 h of MCA occlusion followed by 5 h of reperfusion. Brain surface cooling was induced for 4 h during and after MCA occlusion in the hypothermia group, but not in the normothermia group. Brain surface cooling was performed using saline perfusion into the subdural space. Rectal temperature, brain surface temperature, and deep brain temperature were monitored, and regional cerebral blood flow (rCBF) and somatosensory evoked potential (SEP) were serially measured. After 5 h of reperfusion, water content was also measured. Although the rectal temperature was maintained at about 37 degrees C, the brain surface temperature decreased rapidly to 33 degrees C and was maintained at that temperature. For 3 h following reperfusion, the rCBF was lower in the hypothermia group than in the normothermia group. At 4 and 5 h after reperfusion, the recovery of SEP amplitude was significantly more enhanced in the hypothermia group than in the normothermia group. In the gray matter, the water content was significantly more diminished in the hypothermia group than in the normothermia group. These results demonstrate that our method is useful for protecting the ischemic brain from a transient MCA occlusion. This method may be adapted for neurological surgery.     

颈动脉内膜剥脱术后脑过度灌注综合征围手术期干预分析

目的 探讨颈动脉内膜剥脱术后脑过度灌注综合征围手术期干预。方法 回顾性分析2017年1月~11月我院57例患者因颈动脉狭窄行颈动脉内膜剥脱术后完整病例资料,围手术期监测头颈部CTA或DSA、经TCD、头部MRI,并动态监测患者收缩压,实现围手术期脑过度灌注综合征监测和有效干预。结果 57例患者经术后CTA/DSA证实颈动脉狭窄斑块完整切除,1例（1.75%）患者经临床症状及TCD、MRI影像学证实存在脑过度灌注综合征,出现头痛,手术对侧肢体肌力下降及认知功能下降,经积极控制血压及TCD动态监测,患者于术后7 d恢复正常。所有患者术后7 d无颈部血肿、声音嘶哑、颅内出血、脑缺血发作、植物生存及死亡患者。结论 围手术期加强监测是防治颈动脉内膜剥脱术后脑过度灌注综合征的重要方法,而控制血压是治疗脑过度灌注综合征的有效干预手段。     

浅低温脑灌注在体外循环下小儿室间隔缺损修补术中的应用

目的探讨浅低温脑灌注在体外循环下小儿室间隔缺损修补术中的应用效果。方法回顾性分析2017年2月至2018年7月我院收治的81例行体外循环下小儿室间隔缺损修补术患儿的临床资料,将术中采用浅低温脑灌注治疗的43例患儿设为浅低温组,术中采用中低温下脑灌注治疗的38例患儿设为中低温组。对比2组患儿术中最低鼻咽温度,术中最低直肠温度,术中体外循环时间,术中主动脉阻断时间,术后呼吸支持时间,术后心包和纵隔引流量,麻醉前(T0)、麻醉后10 min(T1)、手术开始后20 min(T2)、手术结束时(T3)血压(BP)及心率(HR)水平变化,术中室颤,术后低血压,术后心律失常及术后短暂性神经功能障碍发生率。结果浅低温组术中最低鼻咽温度、术中最低直肠温度均高于中低温组,差异有统计学意义(P<0.05),2组术中体外循环时间、术中主动脉阻断时间、术后呼吸支持时间、术后心包和纵隔引流量比较差异无统计学意义(P>0.05);各时刻2组间收缩压(SBP)、舒张压(DBP)、HR组间比较差异无统计学意义(P>0.05),且2组SBP、DBP和HR水平均先下降后升高,其中T1、T2、T3时刻BP和HR水平均明显低于T0时刻(P<0.05),T2时刻BP和HR水平均明显低于T1时刻(P<0.05),T3时刻BP和HR水平均明显高于T2时刻,差异均有统计学意义(P<0.05);浅低温组术后心律失常发生率与中低温组均相近,差异无统计学意义(P>0.05),浅低温组术中室颤、术后低血压、术后短暂性神经功能障碍发生率均显著低于中低温组,差异有统计学意义(P<0.05)。结论在体外循环下小儿室间隔缺损修补术中,应用浅低温脑灌注治疗可减少术中室颤、术后低血压及术后短暂性神经功能障碍。     

亚低温对大鼠缺血性脑损伤后SOCS3表达的影响

目的观察大鼠局灶性脑缺血再灌注后不同时间点细胞因子信号转导抑制因子-3(supressor of cytokine signaling 3,SOCS3)的表达情况及实施亚低温后的变化,进一步探讨亚低温的脑保护作用。方法线栓法制作大鼠大脑中动脉栓塞局灶性脑缺血再灌注模型,同时给予亚低温治疗。HE染色观察病理形态改变,免疫组化法检测SOCS3的表达,TUNEL法检测凋亡细胞。结果与假手术组相比,常温缺血组于再灌注3 h后SOCS3的表达开始增强,至24 h达高峰,7天时仍有表达;亚低温缺血组各时间点表达均明显高于常温缺血组(P<0.05);常温缺血组凋亡阳性细胞数随再灌注时间的延长而逐渐增多,至72h达高峰;亚低温缺血组各时间点的表达均明显少于常温缺血组(P<0.05)。结论脑缺血再灌注损伤后SOCS3的表达增强,亚低温可能通过促进SOCS3的表达发挥缺血后抗神经元凋亡的作用。     

Protection by silibinin against experimental ischemic stroke: Up-regulated pAkt,pmTOR, HIF-1α and Bcl-2, down-regulated Bax,NF-κB expression

Inflammation and apoptosis play an important role in cerebral ischemic pathogenesis and may represent a target for treatment. Silibinin has been proved to elicit a variety of biological effects through its anti-inflammatory and anti-apoptotic properties in hepatotoxic, cancer and carcinogenic events. Whether this protective effect applies to ischemic injury in brain is still unknown, we therefore investigated the potential protective role of silibinin in ischemic stroke and the underlying mechanisms. Silibinin was administered intragastric 30 min before permanent middle cerebral artery occlusion (pMCAO). We found that silibinin significantly alleviated neurological deficit, reduced infarct volume, and suppressed brain edema, which were accompanied with upregulation of pAkt, pmTOR, HIF-1α, Bcl-2 and downregulation of Bax, NF-κB in ischemic brain tissue after stroke. Our results show that silibinin might exert anti-inflammatory and anti-apoptotic effects in ischemic brain through activating Akt/mTOR signaling.