人尿液干细胞联合硫酸软骨素酶ABC对脊髓损伤后神经生长因子和脑源性神经营养因子表达的影响

目的探讨大鼠脊髓损伤(spinal cord injury,SCI)后,行人尿液干细胞(human urine-derived stem cells,h USCs)移植以及联合硫酸软骨素酶ABC(chondroitinase ABC,ch ABC)鞘内注射,对脊髓组织神经生长因子(nerve growth factor,NGF)及脑源性神经营养因子(brain-derived neurotrophic factor,BDNF)的影响,以及其相关分子机制。方法取人尿液分离培养h USCs并鉴定。利用Allen法建立大鼠SCI模型;将60只大鼠随机分为5组(n=12),分别为假手术组(A组)、SCI组(B组)、SCI+h USCs组(C组)、SCI+ch ABC组(D组)、SCI+h USCs+ch ABC组(E组)。模型制备后10、20、30 d,利用BBB评分法评价大鼠下肢运动功能;30 d时取脊髓组织,采用实时荧光定量PCR检测及免疫组织化学染色观察NGF、BDNF表达情况,Western blot检测Bax、Bcl-2蛋白表达。结果经鉴定,培养的细胞具有多向分化特性,为h USCs。SCI模型制备后10、20、30 d,B组下肢运动功能BBB评分均显著低于A、C、D、E组,C、D、E组显著低于A组,C、D组低于E组,比较差异均有统计学意义(P0.05)。实时荧光定量PCR及免疫组织化学染色检测示,模型制备后30 d,B组NGF、BDNF表达显著低于A、C、D、E组,C、D、E组显著低于A组,C、D组低于E组,比较差异均有统计学意义(P0.05);C、D组间比较差异无统计学意义(P0.05)。Western blot检测显示,B组Bax蛋白相对表达量明显高于A、C、D、E组,C、D、E组显著高于A组,C、D组高于E组,比较差异均有统计学意义(P0.05);B组Bcl-2蛋白相对表达量显著低于A、C、D、E组,C、D、E组显著低于A组,C、D组低于E组,比较差异均有统计学意义(P0.05)。结论 h USCs对大鼠SCI具有修复作用,通过联合ch ABC可促进SCI修复,其机制可能是通过促进NGF和BDNF表达,抑制神经细胞凋亡,发挥保护作用。     

三七皂苷R1对大鼠脊髓损伤后线粒体功能和神经炎症的作用及相关机制研究

【摘要】 目的：探究三七皂苷R1（notoginsenoside R1,NGR1）对大鼠脊髓损伤（spinal cord injury,SCI）后线粒体功能和神经炎症的作用及相关机制。方法：SPF级2月龄SD雄性大鼠80只,体质量为250～280g,按随机数字表法分为A1组、B1组、C1组和D1组,每组各20只。A1组仅暴露脊髓,B1组、C1组和D1组大鼠采用改良的Allen′s打击法建立急性SCI模型。A1组和B1组腹腔注射生理盐水,C1组、D1组腹腔注射对应剂量的NGR1和ML385[核因子E2 相关因子2（nuclear factor E2 related factor2,Nrf2）抑制剂]。给药1d、2d、3d采用BBB评分法评估大鼠后肢运动功能恢复情况;给药结束后,各取3只大鼠脊髓样本,铬化青染色与TUNEL染色观察大鼠脱髓鞘及细胞凋亡;利用试剂盒评估脊髓组织线粒体功能;ELISA检测脊髓组织炎症因子的表达;免疫荧光双染色检测脊髓组织离子钙结合衔接分子1（ionized calcium binding adapter molecule 1,Iba1）+诱导型一氧化氮合酶（inducible nitric oxide synthase,iNOS）+细胞数;RT-qPCR检测脊髓组织Nrf2、血红素加氧酶-1（heme oxygenase-1,HO-1）mRNA的表达;Western-blot检测脊髓组织Nrf2、HO-1、Bcl2 相关X（BCL2-associated X,Bax）蛋白、细胞淋巴瘤-2（B cell lymphoma-2,Bcl-2）蛋白表达。将购买的PC12细胞分为A2组、B2组、C2组和D2组。A2组正常培养,B2组、C2组和D2组细胞在含H2O2的培养基中培养,C2组和D2组分别加入的NGR1和ML385。各组细胞培养24h后采用CCK8法检测PC12细胞活性;Annexin V-FITC/PI染色检测PC12细胞凋亡;ELISA检测PC12细胞中炎症因子的表达;RT-qPCR检测PC12细胞Nrf2、HO-1 mRNA的表达;Western-blot检测PC12细胞Nrf2、HO-1、Bax蛋白、Bcl-2蛋白表达。结果：与A1组相比,B1组大鼠BBB评分降低,脱髓鞘加重,细胞凋亡增加,超氧化物歧化酶（superoxide dismutase,SOD）活性、Ca2+-Mg2+-ATP酶活性下降,丙二醛（malondialdehyde,MDA）浓度、磷脂酶A2（phospholipase A2,PLA2）活性升高,肿瘤坏死因子-α（tumor necrosis factor-α,TNF-α）、白介素-8 （interleukin-8,IL-8）、白介素-6（interleukin-6,IL-6）水平升高,Iba1+iNOS+细胞数增加,Bax蛋白、Nrf2、HO-1 mRNA和蛋白表达增加,Bcl-2蛋白表达减少（P＜0.05）;与B1组和D1组相比,C1组大鼠BBB评分升高（P＜0.05）,脱髓鞘减轻,细胞凋亡减少,SOD活性、Ca2+-Mg2+-ATP酶活性升高,MDA浓度、PLA2活性降低,TNF-α、IL-8和IL-6水平降低,Iba1+iNOS+细胞数减少,Bax蛋白表达减少,Nrf2、HO-1 mRNA和蛋白、Bcl-2蛋白表达增加（P＜0.05）。与A2组相比,B2组细胞活性降低,细胞凋亡增加,TNF-α、IL-8和IL-6水平升高,Bax蛋白、Nrf2、HO-1 mRNA和蛋白表达增加,Bcl-2蛋白表达减少（P＜0.05）;与B2组和D2组相比,C2组细胞活性升高,细胞凋亡减少,TNF-α、IL-8和IL-6水平降低,Bax蛋白表达减少,Nrf2、HO-1 mRNA和蛋白、Bcl-2蛋白表达增加（P＜0.05）。结论：NGR1能够减轻SCI大鼠脊髓细胞凋亡及氧化应激,促进大鼠运动功能恢复,改善大鼠SCI后线粒体功能和神经炎症;NGR1能够提高PC12细胞活性,抑制其凋亡和炎症水平,其通过激活Nrf2/HO-1信号通路发挥作用。     

芒果苷对大鼠急性脊髓损伤的保护作用及相关机制研究

目的探讨芒果苷对大鼠急性脊髓损伤(spinal cord injury,SCI)的保护作用并分析其相关机制。方法成年雄性SD大鼠90只,体质量250~300 g,随机分为假手术组(A组)、SCI组(B组)、10 mg/kg芒果苷处理组(C组)、25 mg/kg芒果苷处理组(D组)、50 mg/kg芒果苷处理组(E组),每组18只。B、C、D、E组采用Allen法(60 g/cm)建立大鼠T9 SCI模型,A组仅切除T8~10椎板;C、D、E组术后每天按照10、25、50 mg/kg剂量腹腔注射芒果苷,共注射30 d;A、B组于对应时间点注射等量生理盐水。术后观察大鼠存活情况,于24、48、72 h采用BBB评分评价大鼠后肢运动功能;72 h时取损伤节段脊髓测量其水含量,ELISA检测氧化应激反应因子丙二醛(malondialdehyde,MDA)、过氧化氢酶(catalase,CAT)、过氧化物歧化酶(superoxide dismutase,SOD)、谷胱甘肽过氧化物酶(glutathione peroxidase,GSH)以及炎性因子NF-κB、TNF-α、IL-1β、IL-6活性;30 d时取损伤节段脊髓采用ELISA法检测Caspase-3、9活性,Western blot检测凋亡蛋白Bax、Bcl-2表达,组织学观察脊髓组织形态,免疫组织化学染色观察Caspase-3蛋白表达。结果术后各组大鼠均存活至实验结束。B、C、D、E组BBB评分均显著低于A组,B、C、D、E组评分呈逐渐增高趋势,组间比较差异均有统计学意义(P0.05)。B、C、D、E组脊髓水含量均显著高于A组,B、C、D、E组水含量呈逐渐降低趋势,组间比较差异有统计学意义(P0.05)。ELISA检测示,B、C、D、E组MDA、NF-κB、TNF-α、IL-1β、IL-6、Caspase-3、Caspase-9活性均显著高于A组,B、C、D、E组均呈逐渐降低趋势;而CAT、SOD、GSH活性均显著低于A组,B、C、D、E组均呈逐渐增加趋势;以上指标组间比较差异均有统计学意义(P0.05)。Western blot示,B、C、D、E组Bax蛋白表达明显高于A组,B、C、D、E组表达呈逐渐降低趋势;Bcl-2蛋白表达明显低于A组,B、C、D、E组表达呈逐渐增高趋势;组间比较差异有统计学意义(P0.05)。组织学观察示B组脊髓组织符合SCI病理改变,C、D、E组神经坏死程度较B组好转,并且E组效果优于D组,D组优于C组。免疫组织化学染色观察,B、C、D、E组Caspase-3蛋白表达量显著高于A组,B、C、D、E组呈逐渐降低趋势(P0.05)。结论对于大鼠急性SCI,芒果苷可通过减轻脊髓组织水肿、抑制氧化应激反应及炎性反应,调节Bax、Bcl-2蛋白表达,从而发挥神经保护作用。     

不同时间点减压对环扎法所致损伤脊髓Bcl-2、Bax蛋白的表达及意义

目的:探讨不同时间点减压环扎法所致损伤脊髓中神经细胞凋亡及Bax、Bcl-2的表达及其意义。方法:成年SD大鼠84只,随机分为4组:A组,仅行椎板减压及硬脊膜囊周长测量;采用环扎法建立大鼠脊髓损伤模型,B组于环扎术后8h行脊髓减压;C组于环扎术后72h行脊髓减压;D组环扎术后不行脊髓减压。各组分别于术后1d、7d、14d、21d取材,所得脊髓标本行HE染色、Tunel染色及免疫组化法检测Bax、Bcl-2阳性细胞数等情况,并采用BBB评分评价大鼠后肢神经功能变化。结果:Bax染色:B组和C组术后1d开始阳性细胞数增加,7d时达高峰,14d时仍较明显,21d降低;D组术后阳性细胞数持续升高。Bcl-2染色:B组和C组术后阳性细胞数持续升高;D组术后1d阳性细胞数最多,之后持续降低。Tunel染色:B、C及D组术后1d开始出现凋亡细胞,7d时达高峰,以后逐渐减少,21d时仍可见。Bcl-2/Bax值与Tunel阳性细胞数关系:B组和C组二者存在负相关;D组二者呈正相关。BBB评分:A组术后1周后肢运动功能恢复正常;B组和C组术后逐渐升高(P<0.05);D组术后1天开始逐渐降低,7天时最低,然后逐渐升高。结论:环扎法可以建立稳定的大鼠脊髓损伤模型;早期减压能减少继发性脊髓损伤细胞凋亡,有利于神经功能恢复。     

BMSCs移植联合督脉电针对大鼠脊髓损伤后神经功能恢复的影响

目的 探讨骨髓间充质干细胞(BMSCs)移植联合督脉电针对大鼠脊髓损伤(SCI)后神经功能恢复的影响. 方法 从2011年3月至7月,采用全骨髓差速贴壁培养法进行SD大鼠BMSCs的体外分离与培养;利用多中心急性脊髓损伤打击器(MASCIS Impactor)建立大鼠T11脊髓损伤模型,建模成功后将大鼠随机分为4组:对照组(A组)、电针组(B组)、BMSCs移植组(C组)、联合组(D组).SCI后1周,C组与D组大鼠自尾静脉注射移植BMSCs悬液0.1 ml,A组与B组自大鼠尾静脉注射无血清的DMEM/F12培养液0.1 ml,B组与D组接受督脉电针治疗,1次/天.于SCI后1、2、4、8周采用BBB评分法进行后肢运动功能评分;于SCI后8周采用SEP检测脊髓传导功能,采用HE染色观察脊髓空洞大小,采用免疫组化染色检测神经丝蛋白(NF200)的表达.实验中获得的数据采用单因素方差分析. 结果 SCI后2、4、8周,与A组比较,B、C、D组BBB评分均显著升高,差异有统计学意义(P＜0.05);与B、C组比较,D组BBB评分升高更明显,差异有统计学意义(P＜0.05).SCI后8周,与A组比较,B、C、D组SEP潜伏期缩短、波幅增高,差异有统计学意义(p＜0.05);与R、C组比较,D组SEP潜伏期更短,波幅更高,差异有统计学意义(P＜0.05).SCI后8周,4组大鼠脊髓组织损伤区均可见组织结构紊乱,细胞肿胀,空泡变性,且损伤区均可见瘢痕组织及空洞形成,其中A组脊髓空洞最大,B组和C组次之,D组最小.SCI后8周,4组大鼠脊髓组织均有NF200阳性表达,与A组比较,B、C、D组NF200阳性表达增强,差异有统计学意义(P＜0.05);与B、C组比较,D组NF200阳性表达更强,差异有统计学意义(P＜0.05). 结论 BMSCs移植联合督脉电针对脊髓损伤大鼠神经功能恢复的促进作用更为显著,优于单纯BMSCs移植和督脉电针治疗.     

不同时期浅低温对大鼠脑缺血再灌注时谷氨酸、Bcl-2和Bax水平的影响

目的 评价不同时期低温对大鼠脑缺血再灌注时脑组织谷氨酸、Bcl-2和Bax水平的影响.方法 成年雄性SD大鼠24只,随机分为4组(n=6),A组、B组、C组和D组均采用四血管阻断20 min的方法制备全脑缺血再灌注模型.B组、C组和D组均采用鼻咽腔降温的方法维持海马温度32.5～33.5℃1 h,B组降温结束时进行缺血;C组缺血的同时开始降温;D组再灌注的同时开始降温,3组降温结束后开始复温.缺血和再灌注100 min期间每隔10 min收集一次海马CA1区微透析液,测定谷氨酸浓度,反映海马CA1区谷氨酸释放水平.再灌注3 h时,取脑组织,测定海马CA1区Bcl-2和Bax的表达水平,并计算Bcl-2和Bax表达的比值(Bcl-2/Bax).结果 与A组比较,其他3组再灌注期间海马谷氨酸释放水平降低,Bcl-2表达上调,Bax表达下调,Bcl-2/Bax升高(P＜0.05);与B组比较,C组海马Bcl-2表达下调,Bax表达上调,Bcl-2/Bax比值降低(P＜0.05);与C组比较,D组再灌注期间海马谷氨酸释放水平升高,Bax表达上调,Bcl-2/Bax降低(P＜0.05).结论 降温实施越早减轻大鼠脑缺血再灌注损伤的效应越强.     

慢病毒介导的脑红蛋白体内基因转染对兔损伤脊髓的作用

【摘要】　目的：观察慢病毒介导脑红蛋白（Ngb）体内基因转染兔损伤的脊髓组织后对后肢运动功能的影响,探讨其作用机制。方法：用球囊压迫法制成兔脊髓损伤（ＳＣＩ）模型96只,随机分为对照组（A组）、生理盐水组（B组）、空载体组（C组）和Ngb慢病毒组（D组）,每组动物24只,A组SCI后无治疗;B组SCI后向脊髓内注射生理盐水;C组SCI后向脊髓内注射空病毒;D组SCI后向脊髓内注射Ngb重组慢病毒。各组分别在1、3、7、14、21d采用BBB运动功能评分系统检测兔后肢运动功能情况;观察损伤脊髓组织内标记荧光的表达;Real-time PCR和Western blot检测Ngb mRNA及其相应蛋白的表达情况,生化方法检测丙二醛（MDA）和一氧化氮（NO）水平。结果：损伤后14d和21d,D组BBB评分明显高于其他3组（P<0.05）,但A、B及C组之间比较无差异（P＞0.05）;C组和D组兔损伤部位脊髓组织均有GFP表达的绿色荧光信号;损伤后7d、14d和21d,D组的Ngb表达与其他3组比较明显增强（P<0.05）;损伤后7d、14d和21d,D组损伤脊髓组织中MDA、NO含量明显低于其他3组（P<0.05）。结论：慢病毒介导脑红蛋白（Ngb）体内基因转染可使Ngb高表达,可能是通过减轻继发性SCI,从而促进SCI后后肢运动功能的恢复。     

单唾液酸四己糖神经节苷脂乳酸/羟基乙酸共聚物微球对大鼠脊髓损伤后神经功能的影响

目的：探讨经蛛网膜下腔注入单唾液酸四己糖神经节苷脂（monosialotetrahexosylgangliosides,GM-1）乳酸/羟基乙酸共聚物（poly lactic-co-glycolic acid,PLGA）微球对大鼠脊髓损伤（spinal cord injury,SCI）后神经功能的影响。方法：94只成年SD大鼠随机分为4组：微球治疗组（A组）、普通GM-1制剂治疗组（B组）和损伤对照组（C组）各30只,正常对照组（D组）4只。A、B、C组大鼠采用Nystrom法制备T10脊髓压迫损伤模型,伤后即刻开始给药,A组大鼠经蛛网膜下腔一次性注入20μlGM-1PLGA微球悬液（含GM-150μg）,B组大鼠伤后至处死前每24h一次经尾静脉注入GM-1普通制剂30mg/kg,C组大鼠经蛛网膜下腔一次性注入20μl生理盐水,D组大鼠不手术、不给药。A、B、C组大鼠于术后1、3、7、14d进行脊髓运动功能（BBB）评分,术后1、7、14d检测运动诱发电位,术后8h、1d、3d、7d、14d检测大鼠脑脊液中GM-1含量;术后8h、1d、3d、7d、14d处死动物（n=6）,取T10节段脊髓并切片,用HE染色观察脊髓组织学变化,用免疫组化染色方法检测SCI后14d时损伤脊髓组织中NF200表达情况。D组上述各指标的检测不分时间点,只进行1次。结果：各时间点A、B、C组大鼠BBB评分均显著低于D组（P〈0.01）,术后3d、7d、14d时A、B组显著高于C组（P〈0.01）,各时间点A组与B组无显著性差异（P〉0.05）。各时间点A、B、C组大鼠运动诱发电位N1波潜伏期较D组明显延长、波幅明显降低（均P〈0.01）,但术后1d和7d时A、B组N1波潜伏期明显较C组短（P〈0.01）,术后7d和14d时A、B组N1波波幅明显较C组高（P〈0.01）,各时间点A组与B组比较无显著性差异（P〉0.05）。各时间点A、B组大鼠脑脊液内GM-1含量均显著高于C组和D组（均P〈0.01）,术后8h、1d、3d时A组明显高于B组（P〈0.01或0.05）,术后7、14d时A组与B组比较无显著性差异,C组和D组比较无显著性差异（P〉0.05）。HE染色,D组正常,术后各时间点A、B组大鼠脊髓损伤区组织形态优于C组,而A组与B组大鼠脊髓损伤区组织形态基本相似。A组、B组和C组大鼠SCI后14d损伤脊髓组织中NF200阳性细胞平均光密度（AOD）值均显著低于D组（P〈0.01）,但A、B组均显著高于C组（P〈0.01）,A组和B组间无显著性差异。结论：经蛛网膜下腔注入GM-1PLGA微球对大鼠脊髓损伤后神经功能具有良好的保护作用,与外周应用普通GM-1制剂比较,能减少药物用量,快速提高局部药物浓度,并较长时间维持稳定,提高生物利用率,且疗效相当。     

粒细胞集落刺激因子动员BMSCs归巢治疗大鼠脊髓损伤的疗效观察

目的观察粒细胞集落刺激因子(granulocyte colony stimulating factor,G-CSF)动员BMSCs归巢对大鼠脊髓损伤的治疗效果,评估G-CSF动员BMSCs治疗脊髓损伤的可行性。方法将24只成年健康雌性SD大鼠术前12 h于鼠尾静脉注射绿色荧光蛋白(green fluorescence protein,GFP)标记的BMSCs(GFP-BMSCs),并随机分为假手术组(A组)、假手术+G-CSF组(B组)、脊髓损伤组(C组)、脊髓损伤+G-CSF组(D组),每组6只。C、D组采用T10水平脊髓半切法建立脊髓损伤模型,A、B组仅行椎板切除,不损伤脊髓;术后1 h B、D组分别注射G-CSF(10μg/kg·d),连续注射3 d;A、C组注射等量生理盐水。术后1、3、7、14、21、28 d采用BBB评分行大鼠双后肢神经功能评估,并采用ELISA法检测血清TNF-α和基质细胞衍生因子1(stromal cell-derived factor 1,SDF-1)表达。术后28 d处死大鼠取脊髓样品行免疫组织化学染色观察细胞因子SDF-1、BDNF、VEGF和TNF-α表达,免疫荧光染色观察GFP-BMSCs阳性细胞及双染荧光黄色的GFP/神经元核抗原(neuronal nuclei,NeuN)阳性神经元细胞和GFP/胶质原纤维酸性蛋白(glial fibrillary acidic protein,GFAP)阳性神经胶质细胞数;并采用TUNEL法检测细胞凋亡。结果术后各时间点A、B组BBB评分较术前无明显变化;术后1 d,C、D组BBB评分降至最低,后逐渐上升。除术后1 d外,其余各时间点D组BBB评分均显著高于C组(P0.05)。术后3、7、14、21、28 d,C、D组TNF-α和SDF-1含量均明显高于A、B组(P0.05);但D组各时间点TNF-α含量显著低于C组,SDF-1含量显著高于C组(P0.05)。免疫组织化学染色示,术后各时间点C、D组SDF-1、BDNF、VEGF和TNF-α表达均显著高于A、B组(P0.05);D组SDF-1、BDNF、VEGF表达显著高于C组,TNF-α表达显著低于C组(P0.05)。免疫荧光染色示,C、D组GFP-BMSCs、GFP/NeuN、GFP/GFAP阳性细胞数均显著多于A、B组,D组显著多于C组,差异均有统计学意义(P0.05)。TUNEL法检测示,C、D组凋亡细胞数目显著低于A、B组,D组显著低于C组,差异均有统计学意义(P0.05)。结论 G-CSF可以动员BMSCs归巢至大鼠脊髓损伤部位并参与修复,其作用可能与其下调TNF-α减少细胞凋亡,上调SDF-1、BDNF、VEGF促进BMSCs迁移有关。     

抑制TNFR/RIPK信号通路对大鼠急性脊髓损伤后神经功能的影响

目的 :探讨应用坏死性凋亡抑制剂Necrostatin-1(Nec-1)抑制TNFR/RIPK介导的坏死性凋亡信号通路对大鼠急性脊髓损伤(spinal cord injury,SCI)的作用。方法:72只雄性SPF级SD大鼠,体重0.25~0.30kg,随机分为4组:假手术组(Sham组,A组)、假手术+Necrostatin-1组(Sham+Nec-1组,B组)、SCI+二甲基亚砜(DMSO)(DMSO组,C组)、SCI+Nec-1组(Nec-1组,D组)。C、D组采用钳夹法制作大鼠急性SCI模型。所有大鼠硬膜下置管,A组不给药,B组和D组造模后30min经导管注射1μl Nec-1(25μg/μl),C组注射等量DMSO,1次/d,至取材时间点。各组分别于造模后12h、24h和3d三个时间点每组取6只大鼠,先行Basso/Beattie/Bresnahan(BBB)评分,再处死动物取脊髓组织。12h时间点动物处死前1h腹腔注射碘化丙啶(propidine iodide,PI)1mg/kg,取材检测脊髓组织PI红染细胞数;24h时取材采用苏木素-伊红(HE)染色观察脊髓损伤情况、尼氏(Nissl)染色观察神经元存活数目、Western Blot(WB)检测Bcl-2、坏死性凋亡蛋白RIPK1及RIPK3的表达水平;3d时取材行Tunel染色观察细胞凋亡情况。结果:造模后A组和B组各时间点的BBB评分均正常,C、D组各时间点均显著性低于A、B组,D组各时间点的BBB评分均显著高于同时间点C组(P0.05)。造模后12h,D组PI红染细胞较C组明显减少,神经元崩解减轻(P0.05)。造模后24h,A组和B组脊髓组织HE和Nissl染色正常,D组脊髓组织损伤程度和存活神经元数量均优于C组,差异有统计学意义(P0.05);A组和B组Bcl-2、RIPK1及RIPK3均低水平表达,C组RIPK1及RIPK3表达显著性升高,D组Bcl-2表达较C组上调,RIPK1及RIPK3表达显著性下降,C、D两组比较差异均有统计学意义(P0.05)。造模后3d,A组和B组可见少量凋亡小体,C组和D组明显增多,但D组凋亡小体数量较C组明显减少(P0.05)。结论:抑制TNFR/RIPK信号通路可以减轻大鼠急性SCI后的病理变化,改善行为学评分,促进脊髓神经功能恢复。     

Vasopressor hormone response following mesenteric traction during major abdominal surgery

Background : We investigated the vasopressor hormone response following mesenteric traction (MT) with hypotension due to prostacyclin (PGI₂) release in patients undergoing abdominal surgery with a combined general and epidural anesthesia. Methods : In a prospective, randomized, placebo-controlled study we administered 400 mg ibuprofen (i.v.) in 42 patients scheduled for abdominal surgery. General anesthesia was combined with epidural anesthesia (T4-L1). Before as well as 5, 15, 30, 45, and 90 min after MT we recorded plasma osmolality, hemodynamics and measured 6-keto-PGFlα (stabile metabolite of PGI₂), TXB₂ (stabile metabolite of thromboxane A₂) active renin, and arginine vasopressin (AVP) plasma concentrations by radioimmunoassay. Catecholamine levels were assessed by high-pressure liquid chromatography (HPLC) with electrochemical detection. Results : Following MT, arterial hypotension occurred along with a substantial PGI₂ release. This was completely abolished by ibuprofen administration. Although plasma levels of 6-keto-PGF_1α (1133 (708) vs. 60 (3) ng/L, median (median absolute deviation), P=0.0001, placebo vs. ibuprofen) remained significantly elevated, blood pressure was restored within 30 min after MT in the placebo group. At the same point in time plasma concentrations of TXB² (164 (87) vs. 58 (1) ng/L, P=0.0001), epinephrine (46 (33) vs. 14 (6) ng/L, P=0.001), AVP (41 ± (18) vs. 12 (7) ng/L, P=0.0004), and active renin (27 (12) vs. 12 (4) ng/L, P = 0.001) were significantly higher in placebo-treated patients. Conclusion : Under combined general and epidural anesthesia arterial hypotension following MT due to endogenous PGI₂ release is associated with enhanced release of AVP, active renin, epinephrine and thromboxane A₂, presumably contributing to hemodynamic stability within 30 min after MT.     

A Teaspoon Pump for Pumping Blood with High Hydraulic Efficiency and Low Hemolysis Potential

Abstract: Virtually all blood pumps contain some kind of rubbing, sliding, closely moving machinery surfaces that are exposed to the blood being pumped. These valves, internal bearings, magnetic bearing position sensors, and shaft seals cause most of the problems with blood pumps. The original teaspoon pump design prevented the rubbing, sliding machinery surfaces from contacting the blood. However, the hydraulic efficiency was low because the blood was able to "slip around" the rotating impeller so that the blood itself never rotated fast enough to develop adequate pressure. An improved teaspoon blood pump has been designed and tested and has shown acceptable hydraulic performance and low hemolysis potential. The new pump uses a nonrotating "swinging" hose as the pump impeller. The fluid enters the pump through the center of the swinging hose; therefore, there can be no fluid slip between the revolving blood and the revolving impeller. The new pump uses an impeller that is comparable to a flexible garden hose. If the free end of the hose were swung around in a circle like half of a jump rope, the fluid inside the hose would rotate and develop pressure even though the hose impeller itself did not "rotate"; therefore, no rotating shaft seal or internal bearings are required.     

Microspheres Based Detoxification System: A New Method in Convective Blood Purification

Abstract: A variety of protein-bound or hydrophobic substances, accumulating as a result of pathologic conditions such as exogenous or endogenous intoxications, are removed poorly by conventional detoxification methods because of low accessibility (hemodialysis), insufficient adsorption capabilities (hemosorption), low efficiency (peritoneal dialysis), or economic limitations (high-volume plasmapheresis). Combining advantages of existing methods with microspheric technology, a module-based system was designed. Major operating parameters of the latter can be modified to allow for adjustment to individual clinical situations. An extracorporeal blood circuit including a plasmafilter is combined with a secondary high-velocity plasma circuit driven by a centrifugal pump. Different microspheric adsorbers can be combined in one circuit or applied in sequence. Thus, a prolonged treatment can be tailored using specially designed selective adsorber materials. Comparing this system with existing methods (high-flux hemodialysis, molecular adsorbent recycling system), results from our in vitro studies and animal experiments demonstrate the superior efficiency of substance removal.     

Tissue perfusion in relation to cardiac output during continuous positive-pressure ventilation and administration of propranolol or verapamil

Background : Our objective was to determine whether administration of propranolol or verapamil modifies the hemodynamic adaptation to continuous positive-pressure ventilation (CPPV), in particular the regional distribution of cardiac output (CO).
Methods : General hemodynamics and regional blood flows assessed by microsphere technique (15 (μm) were recorded in 16 anesthetized pigs during spontaneous breathing (SB) and CPPV with 8 cm H₂O end-expiratory pressure (CPPV8) before and after intravenous administration of propranolol (0.3 mg · kg⁻¹ followed by 0.15 mg · kg⁻¹ · h⁻¹, n=8) or verapamil (0.1 mg · kg⁻¹ followed by 0.3 mg · kg⁻¹ · h⁻¹, n=8).
Results : CPPV8 depressed CO by 25% without shifts in its relative distribution with the exception of a noteworthy increase in adrenal perfusion. Propranolol increased arterial blood pressure, and due to a fall in heart rate, CO dropped by 25%. The kidneys and, to a lesser extent, the splanchic region and central nervous system received increased fractions of the remaining CO at the expense of skeletal muscle flow. Similar patterns were seen during SB and CPPV8 such that the combination of propranolol and CPPV8 depressed CO by 50%. The circulatory effects of verapamil were less evident but myocardial perfusion tended to increase.
Conclusions : The combination of propranolol or verapamil with CPPV does not result in any specific hemodynamic interaction in anesthetized pigs, except that the combined effect of propranolol and CPPV may severely reduce CO.     

Volatile anaesthetics reduce adhesion of blood platelets under low-flow conditions in the coronary system of isolated guinea pig hearts

Background : Inhibitory effects of volatile anaesthetics on platelet aggregation have been demonstrated in several studies. However, the influence of volatile anaesthetics on intracoronary platelet adhesion has not been elucidated so far.
Methods : Isolated hearts of guinea pigs were perfused with buffer in the absence or presence of volatile anaesthetics (0.5 and 1 MAC) at constant coronary flow rates of 5 ml/min for 25 min, then 1 ml/min for 30 min and again 5 ml/min for 10 min. Before, during and after low-flow perfusion, a bolus of human platelets was applied into the coronary system. To simulate thrombogenic conditions, 0.3 U/ml human thrombin was infused during low-flow perfusion and reperfusion. The number of platelets sequestered to the endothelium was calculated from the difference between coronary in- and output of platelets. The myocardial production of lactate and consumption of pyruvate and coronary perfusion pressure were also determined.
Results : At a flow rate of 5 ml/min only about 3% of the applied platelets did not emerge from the coronary system, in any group. In contrast, 13.1±1.2% (mean±SEM) of infused platelets became adherent in low-flow perfusion in the control group without anaesthetic. The adherence was reduced with each 1 MAC isoflurane (to 6.2±1.2%), sevoflurane (to 4.4±0.9%) or halothane (to 3.2±1.5%) (each P <0.05 vs. control). Volatile anaesthetic, 0.5 MAC, did not inhibit platelet adhesion to a statistically significant extent in any case. Perfusion pressure and metabolic parameters were not statistically different between the control and the hearts exposed to anaesthetics.
Conclusion : Volatile anaesthetics in a concentration of 1 MAC can reduce the adhesion of platelets in the coronary system under reduced flow conditions. This action does not arise from vasodilation or inhibition of ischaemic stress.     

Bariatric Surgery in Some "Central and East-European (former Eastern bloc)"Countries - Current Status and Prediction for the Next Millennium

Background: Obesity is increasing globallly, including in the formerly "Eastern Bloc" countries. Methods: A survey was made of obesity and bariatric surgery. Results: In the 8 East and Central European countries studied, with total population 300 million, roughly 43% of the population was overweight (BMI 25-30), 23% obese (BMI > 30), with about 15 million people morbidly obese (BMI > 40). From 0-10 morbidly obese individuals/100,000/year undergo bariatric surgery. Conclusion: Most countries were found to provide inadequate treatment for obesity.The majority of the morbidly obese are not treated effectively. However, health-care awareness of obesity and bariatric surgeons are slowly increasing.     

Is the recovery profile of mivacurium independent of the rate of decay of its plasma concentration in patients with normal plasma cholinesterase activity?

Background: The duration of action of muscle relaxants is poorly correlated to the rate of decay of their plasma concentration. The plasma concentration of mivacurium may rapidly decrease below its active concentration because of the extensive hydrolysis of mivacurium. By inflating a tourniquet on one upper limb for 3 min after the administration of atracurium, mivacurium or vecuronium, we studied the influence of the initial decline of their plasma concentration on their effect. Methods: In 50 patients anaesthetised with thiopental, isoflurane and fentanyl, the effect of bolus doses of 0.15 or 0.25 mg . kg^?1 mivacurium (MIV 15, MIV 25), 0.3 or 0.5 mg . kg^?1 atracurium (ATR 30, ATR 50) and 0.06 or 0.1 mg . kg^?1 vecuronium (VEC 06, VEC 10) were measured on both arms (evoked response of the adductor pollicis to train-of-four stimulation every 12 s), a tourniquet being applied on one arm just before and during 3 min after the muscle relaxant bolus. Results: Tourniquet inflation of 3 min almost abolished the neuromuscular effect of mivacurium. In the vecuronium groups and in the ATR 50 group, tourniquet inflation did not modify the maximum degree of depression of the twitch response. Also, the duration of action of vecuronium was unaffected by the tourniquet. In the ATR 30 group, times to return of the twitch response to 25% (duration 25%) and 75% (duration 75%) of control response were significantly shorter in the cuffed arm, 23 min vs 27 min, and 41 min vs 45 min, respectively. In the ATR 50 group, only duration 25% was significantly shorter in the cuffed arm (41 min vs 45 min). Conclusion: The results suggest that the rate of decline of the plasma concentration of mivacurium is so rapid, that a very low and almost clinically ineffective concentration is present as soon as 3 min after its administration. The results also indicate that the recovery from a mivacurium-induced neuromuscular blockade is not influenced by the rate of decay of its plasma concentration in patients with genotypically normal plasma cholinesterase.     

Membranes in Artificial Organs

Abstract: Membrane processes play a pivotal and enabling role in modern replacement therapy for acute and chronic organ failure and in the management of immunologic diseases. In fact, virtually all contemporary extracorporeal blood purification methods employ membrane devices, and the next generation of artificial organs and tissue engineering therapies are almost certain to be similarly grounded in membrane technology. In this short essay, we comment on the similarities and differences among synthetic membranes and their natural counterparts and also provide a critical overview of the demographics and technology of hemodialysis, hemofiltration, apheresis, oxygenation, and emerging membrane technologies and applications.     

Influence of dopexamine hydrochloride on haemodynamics and regulators of circulation in patients undergoing major abdominal surgery

Background: Catecholaminergic support is often used to improve haemodynamics in patients undergoing major abdominal surgery. Dopexamine is a synthetic vasoactive catecholamine with beneficial microcirculatory properties. Methods: The influence of perioperative administration of dopexamine on cardiorespiratory data and important regulators of macro- and microcirculation were studied in 30 patients undergoing Whipple pancreaticduodenectomy. The patients received randomized and blinded either 2 μg · kg^?1 · min^?1 of dopexamine (n=15) or placebo (n=15, control group). The infusion was started after induction of anaesthesia and continued until the morning of the first postoperative day. Endothelin-1 (ET-1), vasopressin, atrial natriuretic peptide (ANP), and catecholamine plasma levels were measured from arterial blood samples. Measurements were carried out after induction of anaesthesia, 2 h after onset of surgery, at the end of surgery, 2 h after surgery, and on the morning of the first postoperative day. Results: Cardiac index (CI) increased significantly in the dopexamine group (from 2.61±0.41 to 4.57±0.78 1 · min^?1 · m^?2) and remained elevated until the morning of the first postoperative day. Oxygen delivery index (DO₂I) and oxygen consumption index (VO₂I) were also significantly increased in the dopexamine group (DO₂I: from 416±91 to 717±110 ml/m² · m²; VO₂I: from 98±25 to 157±22 ml/m² · m²), being significantly higher than in the control group. pHi remained stable only in the dopexamine patients, indicating adequate splanchnic perfusion. Vasopressive regulators of circulation increased significantly only in the untreated control patients (vasopressin: from 4.37±1.1 to 35.9±12.1 pg/ml; ET-1: from 2.88±0.91 to 6.91±1.20 pg/ml). Conclusion: Patients undergoing major abdominal surgery may profit from prophylactic perioperative administration of dopexamine hydrochloride in the form of improved haemodynamics and oxygenation as well as beneficial influence on important regulators of organ blood flow.     

Synergistic interaction between the effects of propofol and midazolam with fentanyl on phrenic nerve activity in rabbits

Background: It has been shown that the depressive effects of both propofol and midazolam on consciousness are synergistic with opioids, but the nature of their interactions on other physiological systems, e. g. respiration, has not been fully investigated. The present study examined the effect of propofol and midazolam alone and in combination with fentanyl on phrenic nerve activity (PNA) and whether such interactions are additive or synergistic. Methods: PNA was recorded in 27 anaesthetised and artificially ventilated rabbits. In three groups, propofol, fentanyl and midazolam were administered intravenously in incremental doses to construct dose-response curves for the depressant effects of each one on PNA. In another two groups, the effect of pretreatment with either fentanyl 1 μg · kg^?1 i. v. or midazolam 0.05 mg · kg^?1 i. v. on the effects of propofol and fentanyl respectively on PNA were studied. Results: Propofol and fentanyl caused a dose-dependent depression of PNA with complete abolition at the highest total doses of 16 mg · kg^?1 i. v. and 32 μg · kg^?1 i. v., respectively. In contrast, midazolam in incremental doses to a total of 0.8 mg · kg^?1 reduced mean PNA by 63%, but approximately 12% of PNA remained at a total dose as high as 6.4 mg · kg^?1. The mean ED₅₀s, calculated from dose-response curves, were 5.4 mg · kg^?1, 3.9 μg · kg^?1 and 0.4 mg · kg^?1 for propofol, fentanyl and midazolam, respectively. Initial doses of either fentanyl 1 μg · kg^?1 i. v. or midazolam 0.05 mg · kg^?1 i. v. acted synergistically with subsequent doses of either propofol or fentanyl to abolish PNA at total doses of 8 mg · kg^?1 and 8 μg · kg^?1, respectively. Conclusion: Fentanyl has a synergistic interaction with both propofol and midazolam on PNA and hence potentially on respiration.