烟雾吸入伤大鼠肺组织细胞凋亡及凋亡调控基因表达的变化

探讨细胞凋亡及凋亡调控基因在大鼠烟雾吸入性损伤发生、发展中的作用及意义。以大鼠烟雾吸入伤为模型，应用TUNEL、免疫组化及RT－PCR技术，观察烟雾吸入伤后不同时相肺组织中Bcl-2、Bax、Fas、Fas配体（FasL)基因mRNA及蛋白的表达状态及其与细胞凋亡异常之间的关系。结果显示，烟雾吸入伤后细胞凋亡指数升高；烟雾吸入伤后可上调Bcl-2、Bax、Fas、FasL表达，mRNA表达在12h达峰值，蛋白表达在24h最高。在各时相点Bax、Fas、FasL基因表达与肺组织细胞凋亡有正相关关系。提示烟雾吸入伤后细胞凋亡增加，细胞存活同时受生存基因（Bcl-2)和死亡基因（Bax、Fas、FasL)的双重调控，凋亡相关基因参与了烟雾吸入伤过程细胞凋亡的调控。     

白藜芦醇对大鼠脑创伤后伤区脑组织神经细胞凋亡的影响

目的探讨白藜芦醇（resveratrol，Res）对大鼠脑创伤后神经细胞凋亡的影响及可能的作用机制。方法采用改良的Feeney自由落体脑损伤模型，对颅脑损伤大鼠用Res（50mg／kg，ip）治疗，应用原位末端标记法（TUNEL）及免疫组织化学方法检测受损脑组织治疗前后TUNEL阳性细胞数、Bcl-2及Bax的表达变化。结果治疗组大鼠脑组织TUNEL及Bax表达阳性细胞数低于创伤组及对照组（P〈0．05），Bcl-2表达伤后持续升高，治疗组高于对照组和创伤组（P〈0．05），创伤组和对照组差异不明显（P〉0．05）。结论白藜芦醇具有抗凋亡作用，可能是通过抑制促凋亡因素，促进抑凋亡因素表达来减少颅脑损伤后神经细胞的凋亡，发挥脑保护作用，其详细机制有待进一步研究。     

创伤性脑损伤后脑组织c-fos表达及细胞凋亡

目的研究创伤性脑损伤（TBI）后脑组织c-fos表达及神经细胞凋亡,探讨神经细胞凋亡在脑继发性损害中的作用,及c-fos基因表达与凋亡的关系。方法雄性Wistar大鼠,随机分为假手术对照组和脑创伤后3、12、24、72小时和7天组,采用自由落体撞击致重型颅脑损伤。应用TUNEL法检测神经细胞凋亡,免疫组化法观测c-fos的表达。结果TBI后3小时创伤组各组脑组织即出现c-fos表达和神经细胞凋亡,随伤后时间逐渐增强,至伤后72小时达高峰,伤后7天仍有明显的c-fos表达和神经细胞凋亡。其分布区域为脑挫伤区、挫伤周围皮质和海马,累及细胞类型包括神经元和胶质细胞。c-fos表达与神经细胞凋亡在时序空间分布上基本一致,两者呈正相关。结论创伤性脑损伤可引起脑组织明显的c-fos表达和神经细胞凋亡,c-fos表达增加在神经细胞凋亡和修复中可能起重要作用。     

白藜芦醇对大鼠脑创伤后伤区脑组织神经细胞凋亡的影响

目的 探讨白藜芦醇(resveratrol,Res)对大鼠脑创伤后神经细胞凋亡的影响及可能的作用机制.方法 采用改良的Feeney自由落体脑损伤模型,对颅脑损伤大鼠用Res(50mg/kg,ip)治疗,应用原位末端标记法(TUNEL)及免疫组织化学方法检测受损脑组织治疗前后TUNEL阳性细胞数、Bcl-2及Bax的表达变化.结果 治疗组大鼠脑组织TUNEL及Bax表达阳性细胞数低于创伤组及对照组(P＜0.05),Bcl-2表达伤后持续升高,治疗组高于对照组和创伤组(P＜0.05),创伤组和对照组差异不明显(P＞0.05).结论 白藜芦醇具有抗凋亡作用,可能是通过抑制促凋亡因素,促进抑凋亡因素表达来减少颅脑损伤后神经细胞的凋亡,发挥脑保护作用,其详细机制有待进一步研究.     

自噬相关因子 LC3、Bnip-3和凋亡相关因子Bcl-2、Bax在实验性糖尿病大鼠脑组织中的表达

目的：探讨自噬相关因子LC3、Bnip-3及凋亡相关因子Bcl-2、Bax在实验性糖尿病大鼠脑组织损伤中的作用。方法30只SD大鼠随机分为糖尿病组和对照组。糖尿病组一次性腹腔注射1％链脲佐菌素（60 mg／kg体质量）,对照组一次性腹腔注射柠檬酸缓冲液,饲养12周后活杀大鼠,留取脑组织标本。经HE染色观察其病理学改变,采用免疫组化S-P法检测大鼠脑组织中LC3、Bnip-3、Bcl-2及Bax的表达。结果与对照组大鼠相比,糖尿病大鼠脑组织病理学显示细胞排列紊乱,分布不均,胞体缩小,胞质淡红色,正常形态神经细胞数减少;LC3、Bnip-3及Bax阳性数较对照组明显升高,差异有统计学意义（ P＜0．05）;Bcl-2阳性数较对照组明显降低,差异有统计学意义（P＜0．001）;LC3与Bnip-3呈弱正相关（P＜0．05）,与Bcl-2及Bax不相关;Bnip-3与Bax呈正弱相关（P＜0．05）,与Bcl-2无相关;Bcl-2与Bax无相关。结论糖尿病大鼠脑组织中LC3、Bnip-3及Bax存在过度表达,Bcl-2呈弱表达,表明自噬因子与凋亡因子参与了糖尿病大鼠脑组织损伤的过程,可能是脑组织损伤的机制之一。     

吸入性损伤对小鼠肺组织细胞凋亡的影响

目的探讨细胞凋亡、促凋亡基因和凋亡抑制基因在吸入性损伤发生的作用及意义。方法以小鼠烟雾吸入性损伤为模型，应用RT—PCR和TUNEL技术，观察其损伤后肺组织中Bcl-2和Bax基因mRNA表达及细胞凋亡的变化。结果小鼠烟雾吸入性损伤后肺组织Bcl-2和Bax的表达增加，细胞凋亡指数升高，与对照组相比，差异有非常显著性（P〈0．01）。结论提示细胞凋亡可能参与了吸入性损伤肺组织的病理形成过程。     

氧自由基-线粒体信号通路在Edaravone治疗创伤性脑创伤中的作用

目的 探讨创伤性脑损伤(traumatic brain injury,TBI)后在抗氧化剂Edaravone干预下大鼠大脑皮质凋亡相关蛋白表达改变情况并探讨氧自由基-线粒体信号通路在Edaravone治疗创伤性脑创伤中的作用.方法 成年雄性SD大鼠180只随机分为TBI组、Edaravone治疗组和对照组.每组设伤后1,3,6,24,48,72 h 6个时相点.Edaravone治疗组给予Edaravone(10 mg/kg),对照组、TBI组给予等量等渗盐水.HE染色观察大鼠TBI后皮层神经元的病理改变.免疫组化和TUNEL法以及硫代巴比妥酸缩合法观察不同时相点大鼠皮层Cyt-c、Bcl-2和Bax的表达情况,细胞凋亡和丙二醛(MDA)变化情况.结果 HE染色可见创伤后6 h大脑皮质出现散在变性坏死神经元,伤后24 h达高峰.Edaravone治疗组伤后6 h即可检测到自由基中间产物丙二醛(MDA)的升高,与对照组相比,48 h达高峰.与TBI组相比,MDA含量各时相点均降低,其中在24,48和72 h差异有统计学意义(P＜0.05).与对照组相比,TBI组Cytc阳性细胞免疫反应6 h增强,24 h达高峰,在3,6,24,48和72 h差异有统计学意义(P＜0.05).与TBI组相比,Edaravone治疗组Ctyc阳性细胞免疫反应在24,48和72 h降低.Bcl-2表达在伤后应激性增高,于3 h达高峰,以后逐渐下降.Bax在伤后表达逐渐增高,于48 h达高峰,Bax/Bcl-2于48 h达高峰.TBI后,TUNEL阳性细胞数逐渐增多,24 h以前以TUNEL Ⅰ型细胞为主,24 h后以Ⅱ型细胞为主,并于48 h达高峰.结论 大鼠TBI后皮质神经细胞死亡存在坏死和凋亡两种方式,以凋亡为主.氧自由基-线粒体是TBI后神经细胞凋亡的信号转导通路中的一条.Edaravone对TBI有治疗作用.     

颅脑损伤后脑内中性粒细胞浸润的实验研究

目的 研究大鼠颅脑损伤后脑内中性粒细胞聚集、浸润的时间过程,并探讨与继发性脑损伤的关系。方法 采用改进的Feeney法复制大鼠颅脑损伤模型,将32只健康雄性SD大鼠随机分为假致伤组和致伤组,致伤组于伤后7个不同时相点断头、取脑,行髓过氧化物酶（MPO）活性测定和HE染色。结果 致伤组大鼠脑组织MPO活性表达从伤后3小时开始出现,伤后12～48小时达到高峰,但伤后72小时开始下降,伤后7天降至假致伤组水平。随着中性粒细胞的出现、聚集及浸润,此现象逐渐明显,损伤灶脑组织病理改变加重。结论 颅脑损伤后脑内中性粒细胞的聚集和浸润是颅脑损伤后脑内炎症反应的主要表现,其在继发性脑损伤的病理过程中可能起着重要的作用。     

骨髓间充质干细胞移植治疗大鼠脊髓损伤的抗凋亡机制

目的探讨骨髓间充质干细胞（BMSCs）移植治疗大鼠脊髓损伤的潜在抗凋亡机制。方法成年雄性SD大鼠48只，随机分为对照组、模型组、治疗组，每组16只。模型组、治疗组采用改良Allen法建立大鼠下胸段脊髓损伤模型。造模后7d，于L4～L5间隙蛛网膜下腔向对照组及治疗组注射BMSCs，模型组注射同体积Hank缓冲液。术后评估大鼠后肢运动功能。以原位末端标记法（TUNEL）检测神经细胞凋亡，免疫组织化学染色法检测Bax、Bcl-2的表达。结果BMSCs移植后，治疗组动物后肢运动功能持续恢复。移植后14d，模型组TUNEL阳性细胞数量高于对照组和治疗组（P〈0．01），治疗组亦高于对照组（P〈0．01）；模型组Bax阳性细胞表达多于对照组和治疗组（P〈0．01），治疗组Bax阳性细胞表达多于对照组（P〈0.01），Bcl-2阳性细胞表达各组间差异无统计学意义（P〉0．05）。移植后28d，各组TUNEL阳性细胞数量均减少，模型组仍然高于对照组和治疗组，但差异无统计学意义（P〉0.05）；各组Bax阳性细胞表达减少，各组间比较，差异无统计学意义（P〉0．05），Bcl-2阳性细胞表达变化不明显。结论BMSCs移植可改善脊髓损伤大鼠后肢运动功能，减少神经细胞凋亡，具有潜在抗凋亡作用，这一作用可能通过下调凋亡调控蛋白Bax表达而实现。     

大鼠脑损伤后XIAP与Smac／DIABLO表达的实验研究

目的：观察大鼠颅脑损伤后脑组织中XIAP与Smac／DIABLO表达变化及神经细胞凋亡,探讨颅脑损伤后神经细胞凋亡机制。方法：36只健康雄性Wistar大鼠,随机分为假手术组（sham组）及脑损伤组（TBI组）,采用自由落体法建立大鼠脑损伤模型,用免疫组织化学方法检测XIAP、Smac／DIABLO的表达,TUNEL法检测细胞凋亡。结果：与sham组相比,TBI组XIAP与Smac／DIABLO的表达和TUNEL（＋）细胞数均显著增加（P〈0．05）。结论：颅脑损伤可诱导XIAP与Smac／DIABLO的表达,提示XIAP对脑损伤后神经细胞继发凋亡损害起保护作用,而Smac／DIABLO则促进神经细胞的凋亡。     

Comparison of t2 relaxation in blood,brain, and ferritin

T2 was measured in samples of human blood and monkey brain over a field range of 0.02–1.5 Tesla, with variable interecho times, and was compared with previous data on ferritin solutions (taken with the same apparatus). 1/T2 in deoxygenated blood increased quadratically with field strength, as noted previously, but in brain gray matter the increase was linear, as also was the case in ferritin solution. In both deoxygenated blood and gray matter, 1/T2 increased with interecho time, but appeared to level off at times around 50 msec, as expected from the theory of diffusion through magnetic gradients. Diffusion times estimated by using the chemical exchange approximation were 3.4 msec for deoxygenated blood and 5.7 msec for the globus pallidus. The quadratic field dependence in blood is consistent with this same theory, but the linear dependence in brain tissue and in ferritin solutions remains unexplained.     

影像辅助小切口切除颅内病灶

目的探讨在影像辅助下利用立体定向和导航系统进行手术小切口切除颅内病灶的可行性.方法47例患者术前行CT或MR扫描,分别利用神经导航系统及立体定向仪定出手术切口、骨窗大小,指示手术入路.结果47例患者中26例采用神经导航手术,骨窗平均3.6cm×4.1cm大小;21例采用立体定向环钻开颅术,骨窗直径1.8～4.0cm,所有病变均全切除.结论在影像辅助下采用神经导航系统及立体定向进行手术,有利于减小手术切口和骨窗大小、减少损伤和并发症.     

Characterization of technetium-99m-L,L-ECD for brain perfusion imaging, Part 2: Biodistribution and brain imaging in humans

The safety, biodistribution and kinetics of a new perfusion imaging agent [99mTc-L,L]-ethyl cysteinate dimer (ECD) was evaluated in normal volunteers. Technetium-99m-L,L-ECD is a neutral, lipophilic complex, which is radiochemically pure and stable. Twelve healthy adults were injected with 25-30 mCi of 99mTc-L,L-ECD and imaged periodically for up to 24 hr. Planar imaging showed rapid brain uptake with a peak concentration of 4.9% injected dose and very slow brain washout (approximately 6% per hour during the first 6 hr). Repeat or dynamic tomographic imaging of the brain using either a rotating gamma camera or a multidetector system was performed up to 6 hr postinjection. The distribution of 99mTc-L,L-ECD in the brain did not change and was similar to the pattern seen with other perfusion agents. Background facial areas and lungs cleared rapidly. Peak blood activity was below 10% injected dose at all times and 99mTc-L,L-ECD cleared rapidly through the kidneys. Vital signs, blood and urine chemistries were normal in all volunteers and no adverse reactions were noted. These results suggest that 99mTc-L,L-ECD should be useful for routine assessment of cerebral perfusion in humans.     

Marble brain syndrome: osteopetrosis, renal acidosis and calcification of the brain

Cerebral calcification in children is frequently associated with systemic metabolic disease. We present a case of “marble brain syntrome”, which showed this abnormality.     

Preferential uptake of zinc,manganese, and rubidium in rat brain tumor

The search for radionuclides that can be an index of viability in proliferating cells is important for nuclear medicine diagnosis of brain tumors. On the basis of the finding that 65Zn is preferentially taken up in rat brain tumors, the uptake of various radionuclides was examined in rat brain tumor by using the multitracer technique. Male Fisher rats were intrahippocampally injected with C6 glioma cells. Fourteen days after implantation, the radioactive multitracer solution was injected into the tail vein of tumor-bearing rats. One hour after intravenous injection, the uptake of 65Zn, 83Rb and 54Mn was relatively high in C6 glioma of 15 radionuclides detected, and was much higher than in other brain regions and in the blood. It is likely that rubidium and manganese, in addition to zinc, are preferentially taken up by tumors in the brain.     

Efficacy of whole brain radiotherapy combined with fractionated stereotactic radiotherapy in metastatic brain tumors, and prognostic factors

PURPOSE: We attempted to analyze the effectiveness of whole brain radiotherapy (WBRT) combined with fractionated stereotactic radiotherapy (FSRT) in brain metastases. METHODS: Thirty-seven metastatic brain tumors in 29 patients without previous treatment were treated with WBRT plus FSRT, from October 1996 to February 2002. Four of the patients received stereotactic radiosurgery (SRS) prior to WBRT. Non-small cell lung cancer was the most common type of primary tumor (20/29). The total dose to the whole brain ranged from 30 Gy to 40 Gy, and the boost dose from FSRT ranged from 12 Gy to 40 Gy. End points were survival rate and local control rates. Factors influencing survival were evaluated. RESULTS: Median survival was 13 months, and actuarial survival rates at one and two years were 81% and 39%, respectively. Actuarial one and two year local control rates for all lesions were 78% and 71%, respectively. Survival was significantly associated with age, tumor size, presence of active extracranial tumors, and performance status. No acute or delayed complications were observed. CONCLUSIONS: We believe that WBRT plus FSRT should be included in the treatment options for metastatic brain tumors, and we consider the effect of this non-invasive method to be quite good in patients with good prognostic factors, although other invasive modalities could also be effective in them.