小鼠肝缺血再灌注后Toll样受体2在缺血肝组织中的激活及其意义

目的　探索小鼠肝缺血再灌注后缺血肝组织中Toll样受体 2 (TLR2 )的激活及其与肝功能损伤之间的关系。方法　缺血再灌注损伤组 (I/R组 ),假手术对照组 (S组 )均采用实时荧光定量多聚酶链反应检测肝组织中TLR2mRNA及TLR2蛋白的表达,同时检测门静脉血浆丙氨酸氨基转移酶(ALT)、肿瘤坏死因子α(TNF α)及门静脉血清内毒素 (endotoxin, EN)水平。结果　肝脏部分缺血1h再灌注 4h后,I/R组与S组小鼠缺血肝组织TLR2 mRNA的表达 (ΔCt值 )分别为 1. 0 6±0. 9 1和5. 0 8±1. 3 2, 两组间差异有显著性 (P < 0. 0 1 ),I/R组缺血肝组织TLR2 蛋白的表达 (OD值 )( 4 3 3. 9 1±2 5. 5 3 )水平较S组 ( 1 0 2. 8 6±1 3. 5 8 )显著升高 (P< 0. 0 1 )。I/R组门静脉血清TNF α[ ( 1 1 2. 5 2±1 4. 4 1 )pg/mL]较S组 [ ( 5. 9 6 ±4. 4 3 )pg/mL]显著升高 (P < 0. 0 1 );I/R组ALT[ ( 8 4 8. 3 3±2 7 1. 3 7 )U/L]较S组 [ ( 4 2. 3 9±1 4. 7 5 )U/L]显著升高 (P < 0. 0 1 );而门静脉血清内毒素水平组间差异无显著性 (P> 0. 0 5 )。结论　TLR2mRNA及蛋白在肝脏缺血再灌注过程中缺血肝组织的表达增强, 此变化伴有TNF α的升高及肝功能的损伤。     

缺血预处理对大鼠肝脏低温保存损伤的保护作用

目的　探讨缺血预处理 (IPC)对大鼠肝脏低温保存损伤的保护作用。方法　制备大鼠肝脏离体非循环灌注模型 ,对供肝分别作不同时间的IPC (IPC1组缺血 5min、IPC2 组缺血 10min、IPC3 组缺血 15min) ,而后比较各组供肝的损伤程度。结果　流出液中AST和ALT的水平 ,IPC1组分别为 (4 0 .1± 6.3 )U/L和 (17.1± 0 .5 )U /L ,IPC2 组分别为 (5 3 .6± 3 .7)U/L和 (19.7± 0 .5 )U /L ,均显著低于未预处理 (NPC)组的 (64 .5± 8.2 )U/L和 (2 3 .8± 3 .9)U /L (P<0 .0 5 ) ;IPC1组又显著低于IPC2 组和IPC3 组的 (63 .8± 7.2 )U/L和 (2 2 .8± 2 .5 )U /L (P<0 .0 5 )。LDH水平 ,NPC组、IPC1组、IPC2 组和IPC3 组分别为 (10 4.3± 2 0 .6)U/L、(84.1± 19.7)U /L、(90 .5± 2 1.1)U/L和 (10 3 .1± 18.5 )U /L ,4组间差异无统计学意义 (P>0 .0 5 ) ,但均高于正常组〔(71.5± 18.9)U /L〕 (P<0 .0 5 )。胆汁分泌量及肝组织ATP含量 ,IPC1组分别为 (5 3 .5± 10 .2 ) μl和 (6.15± 0 .65 ) μmol/g ,IPC2 组分别为 (4 1.5± 8.1) μl和 (4 .77± 0 .2 1) μmol/g ,均显著高于NPC组的 (2 2 .8± 9.7) μl和 (2 .62± 0 .3 4) μmol/g (P<0 .0 5 ) ;IPC1组又显著高于IPC2 组和IPC3 组的 (2 7.5± 2 .8) μl和 (2 .61     

缺血预处理对大鼠肝脏缺血再灌注损伤保护作用机制的研究

目的　探讨缺血预处理 (IPC)保护作用的发生机制。方法　建立大鼠部分肝脏热缺血再灌注模型。IPC采用肝脏缺血 10min ,再灌注 10min。结果　IPC后肝组织中腺苷和NO水平明显升高 ,与对照组相比差异显著 (P <0 0 1) ,但IPC前应用腺苷A2 受体拮抗剂后NO的升高被抑制 (P<0 0 1)。缺血再灌注 (I/R) 2h后血清中TNF α、AST、ALT、LDH及W/D水平和假手术组相比明显增加 ,而IL 10含量降低 (P <0 0 1) ;IPC、I/R前加入腺苷、IPC前应用腺苷A1受体拮抗剂显著地降低TNF α释放和AST、ALT、LDH及W /D水平 ,提高IL 10含量 ,与I/R组相比差异显著 (P <0 0 1) ;但IPC前应用腺苷A2 受体拮抗剂 (IPC +A2 antag)和NO合成酶抑制剂NAME并没有能像IPC组那样有效降低TNF α、AST、ALT、LDH及W /D的水平 ,提高IL 10的含量 (P <0 0 1) ;而IPC前给IPC+A2 antag组提供NO前体精氨酸又获得和IPC组同样的结果 (P >0 0 5 )。结论　IPC引起细胞外腺苷水平升高 ,腺苷A2 受体活化 ,介导了NO合成增加 ,最终通过抑制效应器TNF α的释放、增加IL 10的合成来实现对缺血组织的保护作用。     

乌司他丁对兔在体肺缺血再灌注损伤的保护作用

目的　探讨乌司他丁对活体肺缺血再灌注损伤的保护作用。方法　将 2 0只新西兰大白兔随机分成缺血再灌注损伤组 (A组 )和乌司他丁组 (B组 ) ,B组阻断前给乌司他丁 (1 0 0 0 0U/kg体重 )。两组阻断 2h和再灌注 1h后采血检测血气、白细胞介素 6(IL 6)和肿瘤坏死因子 α(TNF α)。摘取左肺测定湿干重比 (W/B)和病理学检查。结果　阻断 2h后 ,两组血氧分压 (PO2 )接近 ;恢复灌注 1h后 ,B组PO2 高于A组 (77.61± 5 .0 4 )mmHg(1mmHg =0 .1 33kPa)和 (1 0 0 .85± 6 .73)mmHg ;TNF α值 (A值 ) ,A组各时段均显著高于B组 (2 54 .0 2± 1 4 .31和 50 4 .0 2± 33 .52比 1 4 8.63± 2 1 .0 6)和 1 60 .54± 1 6 .93) ;A组肺湿干重比高于B组 ;肺外观苍白肿胀 ,病理检查见组织结构损伤。结论　乌司他丁能保护在体肺缺血再灌注中肺组织结构的损伤     

一氧化氮对岛状肌皮瓣缺血再灌注损伤的影响

目的　观察NO对岛状肌皮瓣I/R损伤的影响并探讨其作用机制。方法　选用白色小家猪 15只 ,随机分为I/R组、I/R +NO供体L -arg组及对照组。制作猪腹直肌岛状肌皮瓣I/R模型 ,于再灌注前后给予L -arg ,检测I/R不同时相皮瓣静脉血中NO的间接含量、皮瓣NTR渗出 ,计算再灌注完毕后肌肉存活比例。结果　①I/R +L -arg组再灌注 0 .5小时、1小时NO间接含量 ( 75 .0 7± 12 .5 4 ) μmol/L、( 86.86± 2 0 .15 ) μmol/L ,明显高于I/R组 ( 4 6.75± 11.77) μmol/L、( 4 0 .3 8± 10 .78) μmol/L(P <0 .0 1)。②再灌注 1小时、4小时I/R +L -arg组皮瓣NTR计数 ( 66.5 0± 17.3 3～ 15 3 .80± 3 8.5 3 ) / 2 0个高倍视野明显低于I/R组 ( 171.5 0± 4 4 .5 0 ,3 16.80± 5 2 .85 ) / 2 0个高倍视野 (P <0 .0 1)。③再灌注完毕后 ,I/R +L -arg组皮瓣肌肉的存活比例 ( 83 .70± 15 .60 ) %明显高于I/R组 ( 2 4 .0 7± 12 .3 5 ) % (P <0 .0 1)。结论　于缺血后再灌注前及再灌注早期给予L -arg ,适当增加内源性NO的产生 ,能有效减轻肌皮瓣缺血再灌注损伤。     

缺血预处理和阿霉素预处理对大鼠肝脏低温保存损伤的保护作用

目的研究预处理对大鼠肝脏低温保存损伤的保护作用。方法应用大鼠肝脏离体非循环灌注模型 (IPRL) ,对供肝分别作缺血预处理 (IPC)和阿霉素预处理 (DPC) ,比较各组供肝低温保存损伤的程度。结果流出液中AST和ALT的酶学水平 ,IPC组 (40 1± 6 3、17 1± 0 5 )U L和DPC组 (43 6± 3 7、19 4± 0 8)U L显著低于未预处理 (NPC)组 (6 4 5± 8 2、2 3 8± 3 9)U L(P <0 0 5 ) ;胆汁分泌量及肝组织ATP含量 ,IPC组 (5 3 5± 10 2 ) μl、(6 2± 0 6 ) μmol g和DPC组 (5 0 5± 8 1) μl、(6 0±0 6 ) μmol g显著高于NPC组 (2 2 8± 9 7) μl、(2 6± 0 3) μmol g(P <0 0 5 ) ;肝组织丙二醛 (MDA)的含量 ,IPC组 (4 36± 0 2 6 )nmol g和DPC组 (4 5 1± 0 13)nmol g显著低于NPC组 (6 75± 0 17)nmol g(P<0 0 5 ) ;光镜及电镜结果显示 ,IPC组和DPC组肝细胞损伤的程度显著轻于NPC组 ;而IPC组与DPC组相比较 ,上述指标均无显著性差异 (P >0 0 5 )。结论预处理对供肝低温保存损伤具有明显的保护作用 ,药物预处理可以模拟IPC的效果。药物预处理为临床提供一种安全有效的预处理方法。     

白细胞介素-1介导骨骼肌缺血再灌注损伤的研究

目的　探讨白细胞介素 1(IL 1)介导大鼠骨骼肌缺血再灌注损伤的作用及其机制。方法　 2 4只健康雄性SD鼠 ,随机分为假手术组 :仅行颈外静脉插管术 ;损伤组 :缺血 4h ,再灌注 4h ;干预组 :缺血 4h ,再灌注即刻经静脉导管给与白细胞介素 1受体拮抗剂 (IL 1ra)。采用逆转录 聚合酶链反应 (RT PCR)法测定骨骼肌和肺组织白细胞介素 1β(IL 1β)mRNA表达 ;酶联免疫吸附试验法 (ELISA)测定血浆IL 1β水平 ;比色法检测血浆乳酸脱氢酶 (LDH)、肌酸激酶 (CK )、丙二醛(MDA)和组织过氧化物酶 (MPO )含量及电镜观察组织超微结构的改变。结果　应用IL 1ra后 ,IL 1βmRNA水平明显降低 (骨骼肌 :0 .73± 0 .3 5较 1.2 0± 0 .42 ,P <0 .0 1;肺 :1.15± 0 .2 3较 1.70±0 .3 0 ,P <0 .0 1) ;血浆IL 1β水平显著下降(P <0 .0 1) ;CK (76.77± 18.2 8较 12 7.0 7± 2 8.3 4,P <0 .0 1)、LDH (165 40 .85± 10 2 0 .63较 2 3 3 70 .61± 2 160 .5 4,P <0 .0 1)、MDA (7.2 2± 1.65较 9.73±1.91,P <0 .0 1)和MPO (骨骼肌 :2 .2 4± 0 .3 8较 4.43± 0 .65 ,P <0 .0 1;肺 :1.13± 0 .16较 2 .71±0 .3 2 ,P <0 .0 1)含量均明显降低 ,骨骼肌和肺组织超微结构损伤减轻。结论　骨骼肌缺血 再灌注激发IL 1的生成 ,在介导骨     

肿瘤坏死因子α介导骨骼肌缺血-再灌注损伤的实验研究

目的研究肿瘤坏死因子α(TNF α)介导骨骼肌缺血 再灌注损伤的作用机制。方法2 4只健康雄性SD大鼠 (2 5 0～ 30 0g)随机分成 3组。对照组 :仅行麻醉及颈外静脉插管术 ;损伤组 :左后肢缺血 4h ,再灌注 4h ;治疗组 :缺血 4h ,再灌注 4h ,再灌注即刻经静脉导管给与抗TNF α单克隆抗体。结果损伤组较对照组单核细胞TNF αmRNA转录增加 ,血浆丙二醛 (MDA) (9 9± 1 8)比(5 5± 0 4 )、肌酸激酶 (CK) (12 2± 2 4 )比 (49± 11)、一氧化氮 (NO) (2 70± 98)比 (12 8± 4 6 )、组织过氧化物酶 (MPO) (骨骼肌 4 2 7± 0 5 3)比 (1 2 8± 0 19,肺 2 6 1± 0 12 )比 (0 5 7± 0 0 2 )显著升高 (P <0 0 1) ,骨骼肌和肺组织超微结构发生病理改变。治疗组较损伤组MDA(6 2± 1 2 )比 (9 9± 1 8)、CK(5 8±12 )比 (12 2± 2 4 )、NO(15 4± 5 5 )比 (2 70± 98)、MPO(骨骼肌 2 13± 0 2 1)比 (4 2 7± 0 5 3肺 0 95± 0 0 1)比(2 6 1± 0 12 )水平明显降低 (P <0 0 5 ) ,骨骼肌和肺组织病理损伤减轻。结论骨骼肌缺血 再灌注激发TNF α的生成 ,在介导骨骼肌和肺的损伤中起重要作用     

缺血预处理对大鼠胰腺移植的保护作用

目的　探讨缺血预处理对大鼠胰腺移植的远期保护作用。方法　糖尿病大鼠随机分为缺血再灌注组(I/R组, n= 3 0 )和缺血预处理组(IPC组, n= 3 0 ),两组移植前2d,再灌注后3d和7d随机各杀死6只大鼠,取血查血糖及淀粉酶,同时取胰腺组织行HE染色; 6只大鼠用于观测各种代谢指标。其余6只大鼠用来观察大鼠存活率。结果　IPC组1个月存活率高于I/R组( 5 /6∶3 /6, P< 0. 0 1 );再灌注后IPC组各时间点血糖(P< 0. 0 1 )、血淀粉酶(P< 0. 0 1 )、进食量(P< 0. 0 5 )、排尿量(P< 0. 0 1 )和饮水量(P< 0. 0 5 )均低于I/R组;I/R组移植胰的损伤程度大于IPC组。结论　缺血预处理可增加大鼠胰腺移植的存活率,降低血淀粉酶活性,减轻胰腺的再灌注损伤程度,对大鼠胰腺移植具有保护作用。     

缺血-再灌注期心肌组织及血清白细胞介素-1β和白细胞介素-6的变化

目的　观察家兔缺血 再灌注期心肌组织及血清白细胞介素 1β(IL 1β)、白细胞介素 6(IL 6 )的变化和芬太尼对其影响。方法　 2 4只家兔随机分为假手术组 (C组 )、缺血 再灌注组 (IR组 )和芬太尼组 (F组 ) ,每组 8只。IR组行冠状动脉左前降支阻断 30分钟 ,再灌注 3小时 ;F组缺血前 2 0分钟缓慢静注芬太尼 5 0 μg/kg后 ,以 40 0 μg·kg-1·h-1速度维持 ;C组仅分离血管 ,不阻断血流。三组分别于缺血前 5分钟 (I0 )、缺血 30分钟 (I1)、再灌注 1小时 (R1)和 3小时 (R2 )取颈内静脉血 ,并于实验结束时取心肌组织 ,测定血清及心肌组织中IL 1β和IL 6浓度 ,光镜下观察心肌病理结构变化。结果　F组血清IL 1β在R1时达到峰值 ,为I0 的 2 98倍 (P <0 0 1) ,在R2 时下降 (P <0 0 5 ) ;IL 6在R2 时升高 ,为I0 的 1 33倍 (P <0 0 5 )。IR组血清IL 1β在I1～R2 时增高 ,分别是I0 的2 90、4 85和 3 88倍 (P <0 0 1) ;血清IL 6在R1和R2 时持续升高 (P <0 0 1) ,分别为I0 的 1 5 6、1 74倍。F组心肌组织中IL 1β及IL 6含量较C组增高 ,但明显低于IR组 (P <0 0 1)。光镜下F组心肌中度水肿 ,白细胞散在浸润 ;IR组水肿严重 ,白细胞浸润明显。结论　缺血 再灌注时心肌组织和血清IL 1β、IL 6的合成增加 ,芬太尼可     

CXCR2 regulation of tumor necrosis factor-alpha adherence-dependent peroxide production is significantly diminished after severe injury in human neutrophils

BACKGROUND: Primed neutrophils are thought to play a key role in inflammatory pathology. We have shown though in vitro studies that interleukin (IL)-8 and growth-related oncogene-alpha (GROalpha) (CXCR2-specific chemokines) regulate the respiratory burst via the CXCR2 receptor. We have also shown in vivo, CXCR2 receptors are down-regulated in severely injured patients. Our hypothesis is that regulation of the respiratory burst by CXCR2 is lost after severe injury. METHODS: Patient neutrophils were studied within 24 hours of admission to the hospital; excluded were severe head injury and patients with Injury Severity Score < 16. Patient and normal neutrophils were isolated by Ficoll-Hypaque centrifugation after dextran sedimentation. Neutrophils were plated with buffer, 50 nmol/L IL-8 or GROalpha on fibronectin-coated plates for 15 minutes, then stimulated with 10 ng/mL of TNFalpha. CXCR2 expression was measured by flow cytometry. Receptor function was assessed by calcium mobilization. RESULTS: One female and 10 male patients with an average age of 37 +/- 3 and Injury Severity Score of 24 +/- 5 suffered blunt injury. CXCR2 showed a 32% +/- 7% loss, whereas CXCR1 showed 15% +/- 6% reduction. GROalpha stimulation of patient neutrophils showed 60% +/- 16% decrease in calcium mobilization, whereas IL-8 showed no decline. At 40 minutes, IL-8 and GROalpha significantly inhibited TNFalpha adherence-dependent peroxide production in normal neutrophils (35% +/- 4% and 45% +/- 3%, respectively; p < 0.05). Both IL-8 and GROalpha lost the ability to suppress the respiratory burst in severely injured patients, but GROalpha had a significantly greater loss of this suppression (p = 0.004). CONCLUSION: IL-8 and GROalpha lose the ability to regulate the TNFalpha-induced respiratory burst. This may contribute to neutrophil dysregulation after injury and result in organ injury.     

Ulinastatin suppresses systemic inflammatory response following lung ischemia-reperfusion injury in rats

OBJECTIVE: We sought to investigate whether ulinastatin (urinary trypsin inhibitor) inhibited systemic inflammatory responses following lung ischemia-reperfusion (I/R) injury. MATERIALS AND METHODS: Establishing a steady left lung warm I/R model in rats, we randomly divided 32 animals into 4 groups: sham (n = 8); I/R (n = 8); low-dose ulinastatin (5000 U/kg pre-ischemia) + I/R (n = 8); and high-dose ulinastatin (10,000 U/kg pre-ischemia) + I/R (n = 8). Measured variables included plasma concentrations of tumor necrosis factor-alpha (TNF-alpha), as well as interleukin (IL)-6 and IL-8. RESULTS: The serum concentrations of TNF-alpha, IL-6, and IL-8 in the ulinastatin pretreated groups were markedly decreased compared with those of the I/R group (P < .05). The levels of TNF-alpha, IL-6, and IL-8 were lower in the high-dose ulinastatin group compared with the low-dose ulinastatin group (P < .05). CONCLUSION: Ulinastatin produced dose-dependent attenuation of the systemic inflammatory response of rats following lung I/R injury.     

一氧化氮在急性坏死性胰腺炎大鼠肺损伤中的作用

目的　探讨一氧化氮 (NO)在急性坏死性胰腺炎 (ANP)肺损伤中的作用。　方法12 0只成年SD大鼠随机分为正常对照组、ANP组、精氨酸 (L Arg)组、N 硝基 L 精氨酸甲酯 (L NAME)组、混合预处理组 ,每组 2 4只。逆行性胰胆管注射 3%牛磺酸钠建立ANP大鼠模型。经支气管肺泡灌洗获取肺泡巨噬细胞 (AM) ,检测支气管肺泡灌洗液 (BALF)中蛋白含量、肺组织髓过氧化物酶 (MPO)水平、AM分泌肿瘤坏死因子α(TNFα) ,NO水平及TNFαmRNA、诱导型一氧化氮合酶(iNOS)mRNA表达情况。　结果　ANP大鼠肺损伤随着病情进展而逐渐加重 ;肺组织MPO及BALF蛋白含量逐渐升高 ,12h达最高值 ,分别为 (10 8± 0 6 )U/g和 (2 0 11 0± 10 5 5 ) μg/ml;AM分泌TNFα ,NO水平逐渐升高 ,至 6h达到高峰 ,分别为 (16 2 4 2± 14 9 2 ) pg/ml和 (88 8± 6 5 )μmol/L ,12h又回落。AMTNFαmRNA、iNOSmRNA的表达情况与TNFα,NO的变化趋势相似。L Arg、L NAME、混合预处理三组各指标变化趋势与ANP组相似 ,各组与正常对照组相比 ,均有显著性差异 (P <0 0 5 )。L Arg、L NAME组与ANP组相比 ,L Arg组各指标均升高 ,L NAME组各指标均降低 ,差异亦有显著性 (P <0 0 5 )。　结论　由iNOS介导产生的NO的过量生成促进了ANP所致的肺损伤。加入外源性     

利多卡因后处理对大鼠肺缺血／再灌注损伤的影响

目的研究利多卡因后处理对大鼠肺缺血／再灌注损伤（lung ischemia／reperfusion injury,LI／RI）的作用并探讨其可能的机制。方法80只SD大鼠按随机数字表法分为4组,每组20只：假手术组（Sham组）、缺血,再灌注组[（ischemia／reperfusion,VR）组]、单纯缺血后处理组[（ischemic preconditioning,IPC）组]、利多卡因后处理组（Lidocaine组）。采用夹闭左肺门45min、然后复灌2h的方法建立在体肺棵模型。Lidocaine组再灌注即刻开始以4mg·kg-1·h-1泵入利多卡因,持续再灌注2h。观察肺组织病理学改变,检测支气管肺泡灌洗液（bronchoalveolar lavage fluid,BALF）中肺表面活性蛋白A（pulmonary surfatcantassociated proteinA,SP-A）、肺组织SP-AmRNA和SP-A的浓度。结果肺组织病理学观察发现Lidocaine组的肺水肿和白细胞渗出较I／R组明显减轻。再灌注后Lidocaine组与IPC组BALF中SP-A的浓度分别为（8．68±0．41）和（6．56±0．38）,明显高于I／R组（4．42±0．21）,差异有统计学意义（P〈0．05）;肺组织SP-AmRNA的浓度分别为（1．49±0．12）和（1．26±0．10）,明显高于I／R组（1．05扣．11）,差异有统计学意义（P〈0．05）;肺组织SP-A的浓度分别为（72．5±2．9）和（41．3±3．1）,明显高于I／R组（26．8±2．3）,差异有统计学意义（P〈0．05）;Lidocaine组与IPC组比较,BALF中SP-A、肺组织SP-AmRNA和SP-A的浓度明显升高,差异有统计学意义（P〈0．05）。结论利多卡因后处理可使大鼠I／R肺中SP-A的表达上调、分泌增加,可减轻肺水肿,且效果优于单纯IPC,对在体大鼠LI／RI有保护作用。     

Ischemic preconditioning before lower limb ischemia--reperfusion protects against acute lung injury

OBJECTIVE: Prolonged limb ischemia followed by reperfusion (I/R) is associated with a systemic inflammatory response syndrome and remote acute lung injury. Ischemic preconditioning (IPC), achieved with repeated brief periods of I/R before the prolonged ischemic period, has been shown to protect skeletal muscle against ischemic injury. The aim of this study was to ascertain whether IPC of the limb before I/R injury also attenuates systemic inflammation and acute lung injury in a fully resuscitated porcine model of hind limb I/R. METHODS: This prospective, randomized, controlled, experimental animal study was performed in a university-based animal research facility with 18 male Landrace pigs that weighed from 30 to 35 kg. Anesthetized ventilated swine were randomized (n = 6 per group) to three groups: sham-operated control group, I/R group (2 hours of bilateral hind limb ischemia and 2.5 hours of reperfusion), and IPC group (three cycles of 5 minutes of ischemia/5 minutes of reperfusion immediately preceding I/R). Plasma was separated and stored at -70 degrees C for later determination of plasma tumor necrosis factor-alpha and interleukin-6 with bioassay as markers of systemic inflammation. Circulating phagocytic cell priming was assessed with a whole blood chemiluminescence assay. Lung tissue wet-to-dry weight ratio and myeloperoxidase concentration were markers of edema and neutrophil sequestration, respectively. The alveolar-arterial oxygen gradient and pulmonary artery pressure were indices of lung function. RESULTS: In a porcine model, bilateral hind limb (I/R) injury significantly increased plasma interleukin-6 concentrations, circulating phagocytic cell priming, and pulmonary leukosequestration, edema, and impaired gas exchange. Conversely, pigs treated with IPC before the onset of the ischemic period had significantly reduced interleukin-6 levels, circulating phagocytic cell priming, and experienced significantly less pulmonary edema, leukosequestration, and respiratory failure. CONCLUSION: Lower limb IPC protects against systemic inflammation and acute lung injury in lower limb I/R injury.     

Ischemic preconditioning before lower limb ischemia—reperfusion protects against acute lung injury

Objective: Prolonged limb ischemia followed by reperfusion (I/R) is associated with a systemic inflammatory response syndrome and remote acute lung injury. Ischemic preconditioning (IPC), achieved with repeated brief periods of I/R before the prolonged ischemic period, has been shown to protect skeletal muscle against ischemic injury. The aim of this study was to ascertain whether IPC of the limb before I/R injury also attenuates systemic inflammation and acute lung injury in a fully resuscitated porcine model of hind limb I/R. Methods: This prospective, randomized, controlled, experimental animal study was performed in a university-based animal research facility with 18 male Landrace pigs that weighed from 30 to 35 kg. Anesthetized ventilated swine were randomized (n = 6 per group) to three groups: sham-operated control group, I/R group (2 hours of bilateral hind limb ischemia and 2.5 hours of reperfusion), and IPC group (three cycles of 5 minutes of ischemia/5 minutes of reperfusion immediately preceding I/R). Plasma was separated and stored at −70° C for later determination of plasma tumor necrosis factor-α and interleukin-6 with bioassay as markers of systemic inflammation. Circulating phagocytic cell priming was assessed with a whole blood chemiluminescence assay. Lung tissue wet-to-dry weight ratio and myeloperoxidase concentration were markers of edema and neutrophil sequestration, respectively. The alveolar-arterial oxygen gradient and pulmonary artery pressure were indices of lung function. Results: In a porcine model, bilateral hind limb (I/R) injury significantly increased plasma interleukin-6 concentrations, circulating phagocytic cell priming, and pulmonary leukosequestration, edema, and impaired gas exchange. Conversely, pigs treated with IPC before the onset of the ischemic period had significantly reduced interleukin-6 levels, circulating phagocytic cell priming, and experienced significantly less pulmonary edema, leukosequestration, and respiratory failure. Conclusion: Lower limb IPC protects against systemic inflammation and acute lung injury in lower limb I/R injury. (J Vasc Surg 2002;35:1264-73.)     

Pulmonary expression of inducible heme-oxygenase after ischemia/reperfusion of the lower extremities in rats

BACKGROUND: Expression of inducible heme-oxygenase (HO-1) has been shown to be increased in various inflammatory disorders, which may confer a protective role. The aim of our study was to assess pulmonary expression of HO-1 after ischemia/reperfusion (I/R) of the lower limbs in rats. MATERIALS AND METHODS: We compared three groups of rats (n = 5/group): one Sham group, and two I/R groups (aorta cross-clamped for 2 h followed by 2 h of reperfusion), one of which pre-treated with Zn-protoporphyrin (Zn-PP), a competitive inhibitor of HO (50 micromol/kg, i.p.). At the end of experiment, lungs were harvested for determination of HO activity and HO-1 expression by Western blot and immunohistochemistry. Lung injury was assessed by bronchoalveolar lavage, histological study, and determination of the lung Evans Blue dye content, an index of microvascular permeability. RESULTS: I/R of the lower limbs was responsible for acute lung injury (ALI), characterized by neutrophilic infiltration (87 +/- 20 x 10(3) neutrophils/mm(3), Sham group versus 191 +/- 38 x 10(3) neutrophils/mm(3), I/R group; P < 0.002) and an increase in lung Evans blue dye content: (74 +/- 6 microg/g, Sham group versus 122 +/- 48 microg/g, I/R group; P < 0.05). Pre-treatment with Zn-PP further increases the Evans Blue content (122 +/- 48 microg/g, I/R group versus 179 +/- 23 microg/g Zn-PP group P < 0.05) and the neutrophilic infiltration. Pulmonary heme-oxygenase activity, and HO-1 content were increased after I/R. (10.5 +/- 12 pmol bilirubin/mg protein/h, Sham group versus 101.2 +/- 66 pmol bilirubin/mg protein/h, I/R group; P < 0.02). Immunohistochemistry revealed that the expression of HO-1 was mainly localized to inflammatory cells. CONCLUSIONS: ALI following I/R of the lower limbs in rats is associated with an increase of pulmonary expression of HO-1, inhibition of this expression increase the severity of ALI.     

肺炎支原体肺炎患儿支气管肺泡灌洗液白细胞介素-4、白细胞介素-6、干扰素-γ水平与病情和肺功能的关系

目的:分析肺炎支原体肺炎(MPP)患儿支气管肺泡灌洗液(BALF)中白细胞介素-4(IL-4)、白细胞介素-6(IL-6)、干扰素-γ(IFN-γ)水平与病情和肺功能的关系。方法:选取徐州市儿童医院2019年5月至2020年10月收治的109例MPP患儿(研究组)和102例急性支气管异物患儿(对照组),均实施支气管肺泡灌洗术。研究组MPP患儿根据病情分为轻症组(85例)和重症组(24例),并根据患儿肺功能损伤程度分为肺功能正常组(26例)、轻度损伤组(32例)、中度损伤组(30例)和重度损伤组(21例)。取入组患儿BALF,采用酶联免疫吸附试验(ELISA)检测IL-4、IL-6、IFN-γ水平并进行比较;比较研究组不同病情、不同肺功能损伤患儿BALF中IL-4、IL-6和IFN-γ水平:两组间比较采用成组设计资料t检验;多组间整体比较采用方差分析后组间两两比较采用LSD-t检验。应用Pearson相关分析研究组患儿BALF中IL-4、IL-6、IFN-γ水平与肺功能的关系。结果:研究组患儿BALF中IL-4、IL-6、IFN-γ水平均高于对照组[IL-4:(142.4±24.7)pg/ml vs.(73.2±13.0)pg/ml,t=25.159、P<0.001;IL-6:(56.4±10.3)pg/ml vs.(11.2±2.3)pg/ml,t=43.399、P<0.001;IFN-γ:(90.2±16.3)pg/ml vs.(41.8±6.8)pg/ml,t=27.857、P<0.001]。研究组中重症组患儿BALF中IL-4、IL-6、IFN-γ水平分别为(200.7±36.7)pg/ml、(103.3±16.8)pg/ml和(113.5±21.9)pg/ml,均显著高于轻症组[(125.9±22.4)pg/ml、(43.1±7.8)pg/ml和(83.6±14.1)pg/ml](IL-4:t=12.378、P<0.001,IL-6:t=25.010、P<0.001,IFN-γ:t=8.035、P<0.001),差异有统计学意义。研究组中肺功能正常组患儿BALF中IL-4、IL-6和IFN-γ水平分别为(81.6±15.5)pg/ml、(20.4±4.2)pg/ml和(74.7±11.9)pg/ml,轻度损伤者分别为(102.5±19.9)pg/ml、(48.9±8.2)pg/ml和(89.2±11.1)pg/ml,中度损伤者分别为(145.7±25.2)pg/ml、(60.2±10.2)pg/ml和(95.4±12.8)pg/ml,重度损伤者分别为(273.7±42.1)pg/ml、(106.9±17.6)pg/ml和(103.2±13.2)pg/ml。肺功能轻度、中度、重度损伤组患儿BALF中IL-4、IL-6和IFN-γ水平均高于肺功能正常组(P均<0.05),肺功能中度、重度损伤组患儿以上指标水平均高于肺功能轻度损伤组(P均<0.05),肺功能重度损伤患儿均高于肺功能中度损伤者(IL-4:t=13.581、P<0.001,IL-6:t=11.956、P<0.001,IFN-γ:t=2.117、P=0.039),差异均有统计学意义。研究组患儿BALF中IL-4、IL-6、IFN-γ水平与1秒用力呼气容积(FEV_(1))、用力肺活量(FVC)、呼气流量峰值(PEF)均呈负相关(IL-4与FEV_(1)、FEV_(1)/FVC、PEF相关性:r=-0.834、P=0.025,r=-0.810、P=0.009,r=-0.901、P=0.002;IL-6与FEV_(1)、FEV_(1)/FVC、PEF:r=-0.816、P=0.003,r=-0.795、P=0.012,r=-0.743、P=0.007;IFN-γ与FEV_(1)、FEV_(1)/FVC、PEF:r=-0.756、P=0.012,r=-0.738、P=0.010,r=-0.725、P=0.017)。结论:MPP患儿BALF中IL-4、IL-6和IFN-γ水平均偏高,且3个指标水平与病情、肺功能均有关。     

Clara细胞在兔肺缺血再灌注损伤中的作用

目的 探讨Clara细胞在兔肺缺血再灌注(IR)损伤中的作用.方法 健康家兔24只.随机分为3组(n=8):假手术组(S组)、IR组、肺Clara细胞剥除+IR组(CIR组).CIR组置于萘气体浓度为89.28 mg/m3的气体箱中12 h,S组和IR组置于无萘气体箱中12 h.取出正常饲养24 h后.IR组和CIR组采用阻断左肺门60 min,再灌注120 min的方法制备肺IR模型,S组不予阻断肺门.于再灌注120 min时采集颈动脉血样5 ml,测定血清TNF-α和总蛋白浓度,收集支气管肺泡灌洗液(BALF),计数WBC、中性粒细胞(PMN),计算PMN百分比,取肺组织测定MDA含量和湿/干重比值(W/D比值),观察病理学改变和Clara细胞的分布情况.结果 S组肺泡完整,肺实质无炎性细胞浸润,可见较多的Clara细胞;IR组肺不张伴肺气肿,肺间质增宽水肿,中度炎性细胞浸润,肺泡腔内有淡黄色渗出,渗出物有WBC,亦可见较多的Clara细胞;CIR组炎性细胞浸润严重,肺泡腔内渗出物多.WBC较多,血管腔变窄,甚至出现无复流现象,Clara细胞少见.与S组比较,IR组和CIR组BALF中WBC计数、PMN百分比、血清TNF-α浓度、肺组织MDA含量及W/D比值升高(P<0.05 );与IR组比较,CIR组BALF中WBC计数、PMN百分比、血清TNF-α浓度、肺组织MDA含量及W/D比值升高(P＜0.05).结论 肺IR损伤时兔肺内Clara细胞通过抑制炎性反应产生内源性的保护作用.     

吸入异氟烷对大鼠血浆和肺脏IL-1β和IL-10水平的影响

目的 通过观察吸入异氟烷大鼠血浆和肺脏IL-1β和IL-10水平的变化,探讨异氟烷对肺组织局部和全身炎性反应的影响.方法 雄性Wiser大鼠32只,随机分为4组(n=8):对照组(C组)、异氟烷4 h组(Iso-4 h组)、8 h组(Iso-8 h组)和恢复组(R组).C组仅吸入空气;Iso-4 h组、Iso-8 h组分别吸入40% O2+1.5%异氟烷4、8 h;R组吸入40%O2+1.5%异氟烷8 h后停止吸入异氟烷,继续吸入40%O2 2 h.采集股动脉血样检测血浆白细胞介素-1β(IL-1β)和IL-10浓度;处死大鼠后行支气管肺泡灌洗,收集支气管肺泡灌洗液(BALF),测定IL-1β和IL-10浓度;取右肺组织测定IL-1β mRNA和IL-10 mRNA表达.结果 与C组比较,Iso-4 h组BALF IL-1β浓度升高,肺组织IL-1β mRNA表达上调,Iso-8 h组BALF和血浆IL-1β、IL-10浓度升高,肺组织IL-1β mRNA和IL-10 mRNA表达上调(P<0.05),R组BALF和血浆IL-1β、IL-10浓度、肺组织IL-1β mRNA、IL-10 mRNA表达差异无统计学意义(P>0.05);与Iso-4 h组比较,Iso-8 h组BALF和血浆IL-10浓度升高,肺组织IL-10 mRNA表达上调(P<0.05);与Iso-8 h组比较,R组BALF和血浆IL-1β、IL-10浓度降低,肺组织IL-1β mRNA和IL-10 mRNA表达下调(P<0.05).结论 吸入异氟烷可诱发大鼠一过性肺组织局部和全身炎性反应.