肌苷促进脑损伤后神经功能恢复的实验研究

目的：中枢损伤是目前致残率最高的疾病之一,肌苷对于神经损伤后功能恢复的促进作用已经成为研究热点,本研究拟建立一侧前肢瘫痪的大鼠脑外伤模型,证实肌苷治疗促进中枢损伤后上肢功能恢复的有效性,同时初步探索其机制。方法：建立一侧运动皮层冲击损毁的大鼠模型,通过肢体不对称实验、抓取实验等行为学观察证实其惠侧上肢功能受损,后在实验组进行肌苷药物14天,观察28天内上肢功能的恢复情况,与对照组作对比。证实其行为学上的有效性,同时对损伤侧大脑进行顺行BDA染色,探索其内在机制。结果：通过28天的观察发现经过肌苷治疗的的实验组大鼠肢体不对称实验、抓取实验等行为学评分明显好于隐性对照组,顺行BDA染色证实其有促进损伤周围健存皮层突触再生和代偿的作用。结论：肌苷可以促进中枢损伤后大鼠残存神经元得突触再生,使其大脑能在最大程度上代偿其丧失的功能,该药物可能会成为一种新的中枢损伤治疗的前体药物。     

肌苷发酵液絮凝除菌体的研究

目前国内肌苷生产厂家普遍采用的提取方法是“双柱法”,即先用阳离子柱吸附,然后再用炭柱吸附。该方法不但周期长,工作量大,能耗高,而且提取收率低,一般只有60％左右,使我国肌苷的生产成本大大提高。因此,寻求新的提取方法,降低生产成本,是肌苷生产厂家及有关科技人员所共同关注的问题。肌苷发酵液的除菌体就是新法提取的步骤之一,它可以省去阳离子吸附柱,直接采用炭柱吸附,采用此法可使提取周期大大缩短,降低能耗,提高提取收率。 肌苷菌体较难清除,本研究采用能耗低、易操作,工作量小的絮凝方法,所用的絮凝剂为天然无毒物质,因此沉淀菌体可用作饲料蛋白,起到一举两得的作用。     

利用肌苷发酵废液生产酵母的研究

本课题筛选了适宜在肌苷发酵废液中生长的酵母菌,从中选出了生长量最大的ＣＦ菌。并对利用肌苷发酵废液生产该酵母的条件进行了初步研究。     

综合利用薯芋淀粉生产肌苷的研究

本文报道综合利用野生薯芋属植物盾叶薯芋(Dioscorea zingibensisC.H.wright)和穿龙薯芋(Dioscorea nipponica Makino)中的淀粉生产肌苷(Inosine)的方法。将薯芋原料带水磨碎,在水中筛分得到皂甙淀粉浆,用稀酸水解该物质使淀粉糖化,分离后得到糖液和糖渣。糖液加氮源和无机盐,发酵生产肌苷。糖渣再水解提取薯芋皂甙元。     

利用肌苷发酵废液生产单细胞蛋白的研究

我国在利用微生物降解酒精废液、造纸厂废液和味精厂废液等方面已有许多报道,但是,利用肌苷发酵废液作为底物进行单细胞生产还未见报道。同时,提取肌苷后的发酵废液,其营养成份仍很丰富,其中,还原糖含量约为2％,总氮含量为300mg/L～400mg/L,以及一些无机盐。COD值高达186276mg/L。目前,一般肌苷生产厂都将废液排放掉,这不仅严重地污染了环境,而且造成很大的浪费。有鉴于此,本课题进行了菌种的筛选和驯化以及工艺方面的试验。     

比较L-精氨酸、肌苷对肾脏功能保护的实验研究

探讨L-精氨酸(L-Arg)的肾功能保护作用机制及与肌苷的疗效比较。模拟手术肾损伤模型,分别采用放射免疫法和硝酸还原酶法检测手术前后大鼠不同时期尿液β2-MG、血浆NO含量变化。结果表明L-Arg和肌苷均对肾功能损伤有明显保护作用,L-Arg比肌苷更快地促进肾功能的恢复。     

在大鼠创伤性脑损伤模型中神经干细胞移植对突触素表达的影响

目的探讨神经干细胞（NSCs）移植对创伤性脑损伤（TBI）模型大鼠感觉运动功能的恢复作用及其对损伤脑组织中突触素（SYP）表达的影响。方法体外培养大鼠胚胎皮质NSCs;采用Feeney法制备TBI模型,于造模后72h,移植组采用PKH26荧光示踪剂标记的NSCs直接移植于脑损伤区,对照组以等量生理盐水代替NSCs;分别于移植后不同时间点,采用Gridwalk和Latency试验检测TBI大鼠的感觉运动功能;荧光显微镜下计数移植细胞的存活数量;采用免疫印迹和RT-PCR技术检测脑损伤区及周围组织中SYP的表达。结果 NSCs移植大鼠前、后肢功能分别在移植后第2w和4w恢复至手术前水平,而直到第8w,对照组大鼠后肢功能和通过平板移动时间与NSCs移植组和基线比较仍有显著性差异（P〈0.05）。移植的NSCs随移植时间延长存活数量减少,移植后第4w和8w的存活数分别为6.3%±1.0%和4.1%±0.9%。在移植后的8w期间,移植组脑损伤区及周围组织中SYP的表达均明显高于对照组（P〈0.05）。结论移植的NSCs在TBI脑内能够存活,并明显改善了TBI大鼠对侧肢体的感觉运动功能;NSCs移植促进了脑损伤区及周围组织中SYP的表达,这可能是NSCs移植促进功能恢复的机理之一。     

Change in plasma visfatin level after severe traumatic brain injury

Higher plasma visfatin concentration has been associated with ischemic stroke. Thus, we sought to investigate change in plasma visfatin level after traumatic brain injury and to evaluate its relation with disease outcome. Seventy-six healthy controls and 98 patients with acute severe traumatic brain injury were recruited. Twenty-seven patients (27.6%) died and 48 patients (49.0%) suffered from unfavorable outcome (Glasgow outcome scale score of 1–3) in 6 months. On admission, plasma visfatin level was increased in patients than in healthy controls and was highly correlated with Glasgow Coma Scale score. A multivariate analysis identified plasma visfatin level as an independent predictor for 6-month mortality and unfavorable outcome. According to receiver operating characteristic curve analysis, the predictive value of the plasma visfatin concentration was similar to Glasgow Coma Scale score's. In a combined logistic-regression model, visfatin did not improve the predictive value of Glasgow Coma Scale score. Thus, increased plasma visfatin level is associated with 6-month clinical outcomes after severe traumatic brain injury.     

一种有效区分移植细胞和宿主细胞脑损伤模型的建立

为了区分移植神经细胞和宿主细胞,便于将来在宿主体内对移植细胞进行在体的电生理记录以及其它方面的研究,通过机械损毁的方法,建立了一种特殊的脑损伤模型。结果发现,通过机械损毁的方法,在大鼠大脑皮层形成形态规则的损伤空洞,其模型稳定,重复性好;在空洞内进行干细胞移植,能够长时间存活,移植神经干细胞绝大部分细胞分化为神经元,只有少量细胞分化为胶质细胞,而且移植细胞与宿主细胞分界明显;对移植细胞进行单细胞电生理记录,记录到神经元放电信号。这些结果表明,通过机械损毁的方法,在大鼠大脑皮层成功建立了一个稳定、精确定位移植细胞与宿主细胞界限的脑损伤模型。     

Minocycline improves the functional recovery after traumatic brain injury via inhibition of aquaporin-4

Traumatic brain injury (TBI) is one of the main concerns worldwide as there is still no comprehensive therapeutic intervention. Astrocytic water channel aquaporin-4 (AQP-4) system is closely related to the brain edema, water transport at blood-brain barrier (BBB) and astrocyte function in the central nervous system (CNS). Minocycline, a broad-spectrum semisynthetic tetracycline antibiotic, has shown anti-inflammation, anti-apoptotic, vascular protection and neuroprotective effects on TBI models. Here, we tried to further explore the underlying mechanism of minocycline treatment for TBI, especially the relationship of minocycline and AQP4 during TBI treatment. In present study, we observed that minocycline efficaciously reduces the elevation of AQP4 in TBI mice. Furthermore, minocycline significantly reduced neuronal apoptosis, ameliorated brain edema and BBB disruption after TBI. In addition, the expressions of tight junction protein and astrocyte morphology alteration were optimized by minocycline administration. Similar results were found after treating with TGN-020 (an inhibitor of AQP4) in TBI mice. Moreover, these effects were reversed by cyanamide (CYA) treatment, which notably upregulated AQP4 expression level in vivo. In primary cultured astrocytes, small-interfering RNA (siRNA) AQP4 treatment prevented glutamate-induced astrocyte swelling. To sum up, our study suggests that minocycline improves the functional recovery of TBI through reducing AQP4 level to optimize BBB integrity and astrocyte function, and highlights that the AQP4 may be an important therapeutic target during minocycline treating for TBI.     

切断海马伞对大鼠硬性脑挫伤后运动行为恢复的影响

硬性挫伤运动皮层诱发大鼠偏瘫及其随后的行为代偿是研究中枢神经可塑性的一个理想模型。本工作观察了切断海马伞对脑挫伤后行为恢复的影响。结果表明：与对照组相比,(1)切断海马伞—穹隆通路明显延缓了大鼠运动平衡能力的恢复;(2)切断海马伞—穹隆通路后,银杏类黄酮(FGb)失去了促进脑挫伤后运动平衡能力恢复的作用;(3)原位杂交显示,脑损伤后海马DG(齿状回)和CA3区中生长相关蛋白(GAP—43)mRNA的水平明显提高;(4)FGb促进脑损伤后海马DG和CA3区中的GAP—43mRNA水平的上调。这些信息提示,海马参与脑硬性挫伤后的运动代偿,FGb促进脑损伤后的运动行为的恢复可能与海马相关[动物学报49(2)：211-217,2003]。     

创伤性颅脑损伤脑脊液代谢谱改变及临床意义

目的:探讨创伤性颅脑外伤患者脑脊液中代谢谱的改变及其临床意义。方法:用高分辨率质子核磁共振代谢组学检验创伤性颅脑损伤对脑化学物质和代谢的影响。在重型创伤性颅脑损伤组(n=6),损伤后的脑脊液分析脑代谢的变化,并与轻,中型颅脑损伤组(n=6)相比较。结果:与轻型,中型颅脑损伤组相比,发现了乙酰乙酸,尿酸,3-硝基酪氨酸升高的证据。3组脑脊液中乙酰乙酸,尿酸,3-硝基酪氨酸含量有显著性差异(p<0.01)。结论:颅脑创伤后脑脊液中乙酰乙酸,尿酸,3-硝基酪氨酸值均有不同程度升高,且升高越明显则病情越严重。说明乙酰乙酸,尿酸,3-硝基酪氨酸可作为颅脑创伤病情的监测指标。     

The influence of acceleration loading curve characteristics on traumatic brain injury

To prevent brain trauma, understanding the mechanism of injury is essential. Once the mechanism of brain injury has been identified, prevention technologies could then be developed to aid in their prevention. The incidence of brain injury is linked to how the kinematics of a brain injury event affects the internal structures of the brain. As a result it is essential that an attempt be made to describe how the characteristics of the linear and rotational acceleration influence specific traumatic brain injury lesions. As a result, the purpose of this study was to examine the influence of the characteristics of linear and rotational acceleration pulses and how they account for the variance in predicting the outcome of TBI lesions, namely contusion, subdural hematoma (SDH), subarachnoid hemorrhage (SAH), and epidural hematoma (EDH) using a principal components analysis (PCA). Monorail impacts were conducted which simulated falls which caused the TBI lesions. From these reconstructions, the characteristics of the linear and rotational acceleration were determined and used for a PCA analysis. The results indicated that peak resultant acceleration variables did not account for any of the variance in predicting TBI lesions. The majority of the variance was accounted for by duration of the resultant and component linear and rotational acceleration. In addition, the components of linear and rotational acceleration characteristics on the x, y, and z axes accounted for the majority of the remainder of the variance after duration.     

Minocycline attenuates neuronal apoptosis and improves motor function after traumatic brain injury in rats

Minocycline is a type of tetracycline antibiotic with broad-spectrum antibacterial activity that has been demonstrated to protect the brain against a series of central nervous system diseases. However, the precise mechanisms of these neuroprotective actions remain unknown. In the present study, we found that minocycline treatment significantly reduced HT22 cell apoptosis in a mechanical cell injury model. In addition, terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) staining confirmed the neuroprotective effects of minocycline in vivo through the inhibition of apoptosis in a rat model of controlled cortical impact (CCI) brain injury. The western blotting analysis revealed that minocycline treatment significantly downregulated the pro-apoptotic proteins BAX and cleaved caspase-3 and upregulated the anti-apoptotic protein BCL-2. Furthermore, the beam-walking test showed that the administration of minocycline ameliorated traumatic brain injury (TBI)-induced deficits in motor function. Taken together, these findings suggested that minocycline attenuated neuronal apoptosis and improved motor function following TBI.