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981.
树突状细胞在小儿哮喘发病机制中的作用 总被引:3,自引:0,他引:3
Jiang DB Zhou YD Yang XQ Li HQ Yao ZK Qin SW Pan F Zhao JN Zhou P Tang SF 《中华儿科杂志》2004,42(7):520-523
目的 探讨树突状细胞 (DC)在小儿哮喘发病中的可能作用及机制。方法 以Thomas法 ,采用粒 巨噬细胞集落刺激因子 ,白细胞介素 4 (IL 4 )和肿瘤坏死因子α(TNF α)联合培养诱导哮喘患儿外周血DC细胞 ,进而检测DC协同刺激分子B7 1(CD80 )、B7 2 (CD86)的表达 ,DC诱导自体T淋巴细胞的增殖反应 ,以及其分泌的IL 10、IL 12等水平的变化。结果 哮喘患儿外周血DC诱导自体T淋巴细胞增殖反应明显高于对照组 (cpm值分别为 115 6 0± 12 6和 6 5 39± 12 6 ,t =12 1 6 96 ) ,差异有非常显著意义 (P <0 0 1) ;其分泌IL 10水平 [( 3 6± 0 3) μg/L]明显低于对照组 [( 6 9± 0 8) μg/L],差异有非常显著意义 (t=2 0 6 0 8,P <0 0 1) ;分泌IL 12水平 [( 2 9 7± 8 4 )ng/L]也明显低于对照组 [( 4 5 2± 9 8)ng/L],差异有非常显著意义 (t=5 979,P <0 0 1) ;同时 ,哮喘患儿外周血人类白细胞抗原DR( 19 9± 1 3)和协同刺激分子B7 2 (CD86)的表达水平 ( 36 3± 14 0 )明显高于对照组( 10 6± 1 5和 2 4 7± 8 5 ) ,差异有非常显著意义 (t分别 =2 3 30 1和 3 314 ,P均 <0 0 1)。结论 DC可能通过诱导TH1/TH2细胞分化在小儿哮喘发作时起重要作用。其可能的机制系通过DC分泌的细胞因子而起作用。 相似文献
982.
Lok IH Lee DT Yip SK Shek D Tam WH Chung TK 《American journal of obstetrics and gynecology》2004,191(2):546-550
OBJECTIVE: The purpose of this study was to evaluate 12-item General Health Questionnaire (GHQ-12) in screening for psychiatric morbidity after miscarriage. STUDY DESIGN: A prospective cohort study was carried out involving 222 patients. Six weeks after miscarriage, the GHQ-12 was applied. Psychiatric "case" or "non-case" was diagnosed by the psychiatrist with use of the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders-III-R. The patients were computer randomized into Groups A or B. A receiver operating characteristic (ROC) curve was constructed for Group A. The optimal cutoff value of GHQ-12 was determined, and this value was applied to Group B. The test characteristics were assessed. RESULTS: Twenty-seven patients were found to be psychiatric cases. An ROC with area under curve of 0.93 (95% CI 0.87-0.99, P<.001) was constructed. The best GHQ-12 cutoff score was > or =4 in detecting psychiatric caseness. A sensitivity of 83%, specificity of 90%, positive predictive value of 50%, and negative predictive value of 98% were obtained. CONCLUSION: GHQ-12 is an effective screening tool in detecting psychiatric morbidity after miscarriage. 相似文献
983.
984.
Yamashita H Akamine S Sumida Y Inoue M Sawada T Nagayasu T Oka T 《The Annals of thoracic surgery》2004,78(1):292-297
Background
Lung ischemia-reperfusion injury occurs after lung transplantation and various clinical procedures. Recently, apoptosis was reported to be induced after ischemia-reperfusion. We investigated the effects of inhaled nitric oxide (NO) on lung ischemia-reperfusion and apoptosis after ischemia-reperfusion.Methods
As a control group, the left pulmonary hilum of Japanese white rabbits (n = 10) was occluded for 120 minutes and reperfused for 120 minutes. In the inhaled NO group (n = 10), 20 parts per million nitric oxide was inhaled during reperfusion. The sham-operated group was ligated at the right hilum and perfused by the left lung only for 120 minutes. The mean pulmonary arterial pressures and Pao2 were measured during reperfusion. The wet-to-dry weight ratio of the left lower lobe of the lung was calculated. The number of apoptotic cells was estimated using the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL) technique. The TUNEL staining for a time course study was done using 15 control animals that were killed by exsanguination at 15, 30, and 60 minutes after reperfusion.Results
After 120 minutes of reperfusion, the mean pulmonary arterial pressures in the control group and in the inhaled NO group were 23.0 ± 3.2 mm Hg and 13.6 ± 2.4 mm Hg, respectively (p < 0.01). At the same time point, the Pao2 in the control group and in the inhaled NO group were 46.1 ± 15.9 mm Hg and 88.1 ± 14.7 mm Hg, respectively (p < 0.01). The wet-to-dry weight ratios in the control group and in the inhaled NO group were 0.856 ± 0.024 and 0.808 ± 0.006, respectively (p < 0.01). Apoptotic cells appeared in the early phase of reperfusion (after 15 minutes' reperfusion). The number of apoptotic cells was significantly lower in the inhaled group than in the control group after 120 minutes' reperfusion (1.76% versus 2.87%, p < 0.01).Conclusions
Our results suggest that the inhaled NO prevents lung ischemia-reperfusion injury and attenuates apoptosis after reperfusion in the rabbit lung. 相似文献985.
BACKGROUND: Interleukin 12 (IL-12) gene therapy is an effective antitumor agent in local and metastatic murine tumor models. We sought to evaluate the antimetastatic effect of IL-12 cDNA in a liver metastases model. MATERIALS AND METHODS: A liver metastases model was induced by creating a "primary" splenic tumor through inoculation of 1 x 10(5) TS/A adenocarcinoma cells directly into the inferior pole of the spleen in female BALB/c mice. On day 4, 50 microg of IL-12 cDNA or control plasmid DNA was injected into splenic tumor, followed by splenectomy on day 8. Mice were sacrificed on day 25 to assess liver tumor burden. IL-12 mRNA and mIL-12 and IFN-gamma protein levels were assessed after IL-12 injection. Peripheral blood CD4+, CD8+, and NK cells were quantified on day 14 using FACS. To determine the significance of site of cytokine DNA injection, IL-12 cDNA was injected on day 4 into splenic tumor or into the non-involved spleen after isolation of the inferior and superior portions of the spleen, respectively, with surgical clips. Splenectomy was performed on day 8 and sacrifice was performed on day 25. RESULTS: IL-12 mRNA was detected in the liver 8 h after injection, with a peak at 24 h. After splenic injection, protein levels of IL-12 and IFN-gamma were detectable in the liver and spleen 24 h after treatment. IL-12 and IFN-gamma were not detectable in control animals. In the peripheral blood, there was a marked increase in NK cells (13% of total lymphocytes versus 4%, control) and in the CD4+/CD8+ ratio (5.5 versus 1.9). At day 25, there was a marked antimetastatic effect after IL-12 injection into either splenic tumor [liver:body weight, 6.2 versus 10.9 (control), P = 0.007] or non-involved spleen (6.8 g versus 10.7 g, P = 0.005). There was no difference in the antimetastatic effect between animals injected into splenic tumor or non-involved spleen (P = 0.3). CONCLUSION: Injection with a single dose of IL-12 cDNA into splenic tumor or non-involved spleen resulted in a profound antimetastatic effect. Splenic IL-12 injection results in mRNA expression in the liver, protein expression in the liver and spleen, and a marked increase in NK cells and the CD4+/CD8+ ratio in peripheral blood. 相似文献
986.
987.
Endotracheal calcineurin inhibition ameliorates injury in an experimental model of lung ischemia-reperfusion 总被引:3,自引:0,他引:3
Woolley SM Farivar AS Naidu BV Rosengart M Thomas R Fraga C Mulligan MS 《The Journal of thoracic and cardiovascular surgery》2004,127(2):376-384
OBJECTIVES: We previously demonstrated that calcineurin inhibitors given intravenously ameliorate experimental lung ischemia-reperfusion injury. This study evaluates whether these effects can be achieved when these agents are delivered endotracheally. METHODS: Left lungs of Long Evans rats were rendered ischemic for 90 minutes and reperfused for up to 4 hours. Treated animals received tacrolimus endotracheally at doses of 0.2, 0.1, or 0.025 mg/kg 60 minutes before ischemia. Injury was quantitated in terms of vascular permeability. Additional animals treated at a dose of 0.1 mg/kg were assessed for lung tissue myeloperoxidase content and bronchoalveolar lavage leukocyte content. Bronchoalveolar lavage fluid was assessed for cytokine and chemokine content by enzyme-linked immunosorbent assay. Tissue samples were processed for nuclear factor-kappaB activation, and blood levels of tacrolimus were measured in treated animals. RESULTS: Left lung vascular permeability was reduced in treated animals in a dose-dependent fashion compared with controls. The protective effects correlated with a 47% (0.50% +/- 0.06% vs 0.27% +/- 0.08%, respectively) reduction in tissue myeloperoxidase content (P <.004) and marked reductions in bronchoalveolar lavage leukocyte accumulation. This protection was also associated with decreased nuclear factor-kappaB activation and diminished expression of proinflammatory mediators. Blood tacrolimus levels in treated animals at 4 hours of reperfusion were undetectable. CONCLUSIONS: Tacrolimus administered endotracheally is protective against lung ischemia-reperfusion injury in our model. This protection is associated with a decrease in nuclear factor-kappaB activation. This route of tacrolimus administration broadens its potential clinical use and decreases concerns about systemic and renal toxicity. It may be a useful therapy in lung donors to protect against lung ischemia-reperfusion injury. 相似文献
988.
Bronchoscopic surfactant administration preserves gas exchange and pulmonary compliance after single lung transplantation in dogs 总被引:3,自引:0,他引:3
Friedrich I Börgermann J Splittgerber FH Brinkmann M Reidemeister JC Silber RE Seeger W Schmidt R Günther A 《The Journal of thoracic and cardiovascular surgery》2004,127(2):335-343
BACKGROUND: Surfactant abnormalities have been implicated in reperfusion injury and respiratory failure in lung transplantation. METHODS: We investigated the efficacy of bronchoscopic administration of a bovine natural lung surfactant extract (Alveofact) to improve gas exchange and lung mechanics after heterologous left lung transplantation in foxhounds (+4 degrees C ischemia for 24 hours, conservation with Euro-Collins solution). Animals received either no surfactant therapy (untreated controls, n = 6) or 50 mg/kg body weight (prior to explantation, only graft) and 200 mg/kg body weight Alveofact (immediately after reperfusion, both lungs, n = 6). After lung transplantation, separate but synchronized ventilation of each lung was performed in a volume-controlled, pressure-limited mode for 12 hours, with the animals prone. Small catheters were inserted into the pulmonary veins of both the graft and the recipient's native lung for separate blood gas analysis. In the control group, marked protein leakage, influx of neutrophils into the alveolar space, and pulmonary edema formation (extravascular lung water; wet/dry ratio) were encountered in the transplanted lung but only to a very minor extent in the recipient's native lung. RESULTS: Lung compliance values and arterial oxygenation progressively deteriorated in the transplanted but not in the native lungs. Pulmonary hemodynamics did not change significantly. Surfactant administration did not significantly influence the development of reperfusion edema, protein leakage, and neutrophil influx into the grafts. However, surfactant restored the surface activity and the gas exchange (PaO2/FIO2 of 201.2 +/- 20.2 mm Hg vs 119.8 +/- 21.7 mm Hg in controls; P <.05) in the transplanted lungs, and compliance was markedly improved in the surfactant-treated animals (18.8 +/- 1.8 mL/mbar vs 11.5 +/- 1.6 mL/mbar in the controls; P <.05). CONCLUSION: Bronchoscopic surfactant administration does not prevent leukocyte influx or vascular leakage but does protect against respiratory failure and improves lung mechanics in single lung transplantation in dogs. 相似文献
989.
990.
再生小室内间断给予蛋白激酶C激动剂对周围神经表达NGF及损伤修复的影响 总被引:2,自引:2,他引:0
目的探讨大鼠坐骨神经再生小室内间断给予蛋白激酶C激动剂-佛波醇酯(phorbol-12-myristate-13-acetate,PMA)后,坐骨神经蛋白激酶C(protein kinase C, PKC)mRNA、神经生长因子(nerve growth factor, NGF)mRNA表达变化规律及轴突数目变化. 方法 SD大鼠42只行双侧坐骨神经中段切断约5 mm,"T"形硅胶管套接,随机分为6组,分别为损伤1、3天,1、2、3和4周组.右侧间断给予1×10-9mol/L PMA(PMA侧);左侧注射等量生理盐水(对照侧).采用组织切片核酸原位杂交(in situ hybridization,ISH)技术检测各组术后各不同点PKC mRNA和NGF mRNA在坐骨神经表达的动态变化及轴突数目变化. 结果对照侧大鼠坐骨神经PKC mRNA在损伤后表达上调,第2周达高峰后下降;NGF mRNA在损伤后表达上调,第3周达高峰值后下降.PMA侧PKC mRNA于第2、3和4周表达较对照侧明显增高,差异有统计学意义(P<0.01或P<0.05);NGF mRNA第2、3和4周表达也较对照侧明显增强,差异有统计学意义(P<0.01).轴突数目在2、3和4周时多,差异有统计学意义(P<0.01). 结论 PKC介导了周围神经损伤修复中的NGF mRNA表达及神经再生,而且PMA能够促进NGF mRNA表达及促进轴突生长. 相似文献