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51.
BACKGROUND: Adhesion molecules such as intercellular adhesion molecule-1 (ICAM-1) are thought to contribute to the airway inflammation and airway hyper-responsiveness (AHR) of allergic asthma. Some differences from allergic asthma have been noted, including airway neutrophilia, and the involvement of ICAM-1 in toluene diisocyanate (TDI) asthma is currently unclear. OBJECTIVE: We utilized mice lacking ICAM-1 expression (ICAM-1(-/-)) to investigate the role of ICAM-1 in airway inflammation and AHR in TDI-induced asthma. METHODS: Male C57BL/6J mice (ICAM-1(+/+)) and ICAM-1(-/-) mice were intranasally sensitized to TDI solution or solvent alone. Airway inflammation, AHR and cytokine secretion were assessed 24 h after challenge by TDI or solvent. The production of antigen-specific IgG and IgE by TDI sensitized and non-sensitized mice was determined. RESULTS: TDI challenge to ICAM-1(+/+) mice induced an increase in airway inflammatory cell numbers, AHR and cytokine secretion of TNF-alpha, macrophage inflammatory protein-2 (MIP-2), IL-4, IL-5 and IFN-gamma into the bronchoalveolar lavage fluid. All these pathophysiological changes were reduced in ICAM-1(-/-) mice. Serum levels of TDI-specific IgG and IgE of ICAM-1(-/-) and ICAM-1(+/+) mice were comparable. CONCLUSION: These results suggest that ICAM-1 plays an essential role in airway inflammation and AHR in TDI-induced asthma.  相似文献   
52.
丹参对脑缺血再灌注区白细胞与内皮细胞粘附的影响   总被引:3,自引:0,他引:3  
目的:研究丹参对脑缺血再灌注损伤后局灶区白细胞与内皮细胞粘附性变化及影响;方法:通过免疫荧光标记技术和显微超高速系统观察脑缺血再灌注及应用丹参后局灶白细胞粘附性的变化。结果:试验表明脑缺血再灌注损伤局部灶区微动脉白细胞附壁指数升高,白细胞与内皮细胞间断裂应力降低,粘附性显著下降。结论:研究结果表明,丹参可显著减轻脑缺血再灌注损伤后内皮细胞的粘附。  相似文献   
53.
BACKGROUND: Histamine plays an important role in vascular disease. Tissue factor (TF) expression is induced in vascular inflammation and acute coronary syndromes. OBJECTIVES: This study examined the effect of histamine on tumor necrosis factor-alpha- (TNF-alpha-) vs. thrombin-induced endothelial TF expression. METHODS AND RESULTS: Histamine (10(-8)-10(-5) mol L-1), TNF-alpha (5 ng mL-1), and thrombin (1 U mL-1) induced TF expression in human endothelial cells. Although TF expression by TNF-alpha and thrombin was identical, histamine augmented TNF-alpha-induced expression 7.0-fold, but thrombin-induced expression only 2.6-fold. Similar responses occurred with TF activity. The H1-receptor antagonist mepyramine abrogated these effects. Differential augmentation by histamine was also observed at the mRNA level. Histamine-induced p38 activation preceded a weak second activation to both TNF-alpha and thrombin. Histamine-induced c-Jun NH2-terminal kinase (JNK) activation was followed by a strong second activation to TNF-alpha, and less to thrombin. Selective inhibition of this second JNK activation by SP600125 reduced TF induction to histamine plus TNF-alpha by 67%, but to histamine plus thrombin by only 32%. Histamine augmented TNF-alpha- and thrombin-induced vascular cell adhesion molecule 1 (VCAM-1) expression to a similar extent. Consistent with this observation, VCAM-1 induction to TNF-alpha and thrombin was mediated by p38, but not by JNK. CONCLUSIONS: Histamine differentially augments TNF-alpha- vs. thrombin-induced TF expression and activity, which is mediated by the H1-receptor, occurs at the mRNA level, and is related to differential JNK activation.  相似文献   
54.
水蛭注射液对大白鼠血小板粘附和血小板聚集功能的影响   总被引:6,自引:1,他引:5  
目的 探讨水蛭注射液对大白鼠血小板粘附性和聚集性的影响。方法 采用大白鼠 2 4只 ,随机分成两组 ,实验组给药 ,对照组以实验组同样的方法和剂量给予生理盐水 ,5d后由颈总动脉取血 ,做血小板粘附性和聚集性试验。结果 水蛭注射液对大鼠血小板粘附性和聚集性具有显著的抑制作用 ,实验组与对照组抑制率有显著的统计学意义 (P <0 0 0 1)。结论 水蛭注射液能够抑制大白鼠血小板的粘附和聚集。  相似文献   
55.
BACKGROUND : Selectins participate in the initial phase of leucocyte migration from circulation to inflamed tissues and may play a role in inflammatory cellular influx into airways in asthma. In the sheep asthma model, TBC1269, a pan-selectin antagonist, reduced late allergen response by 74%. OBJECTIVE : To determine whether a single dose of TBC1269 inhibits early (EAR) and late (LAR) asthmatic responses, and whether it inhibits sputum leucocyte influx after inhalation allergen challenge in atopic asthmatic subjects treated with bronchodilators only. METHODS : Twenty-one asthmatic subjects (mean+/-SD, age=32.5+/-6.7 years, 8 males, FEV1 percent predicted=84+/-15%) with known late asthmatic response based on a screening inhalation allergen challenge were randomly assigned to receive intravenous treatment with either placebo (n=11) or TBC1269 (n=10, 30 mg/kg) infused over 15 min immediately prior to a second (post-treatment) allergen challenge at least 4 weeks after the screening challenge. After each challenge, EAR and LAR were monitored for 7 h. In addition, sputum was induced 1 day before and 1 day after each allergen challenge. RESULTS : TBC1269 did not attenuate the EAR compared with placebo (largest fall in FEV1 within 1 h of 34.1+/-13.9% vs. 31.8+/-12.2% for TBC1269 and placebo groups respectively, P=0.61) or the LAR (largest fall in FEV1 between 3 and 7 h of 39.3+/-15.3% vs. 32.6+/-13.8%, P=0.24). TBC1269 had only minor effects on allergen-induced sputum eosinophilia. CONCLUSION : We conclude that TBC1269 administered before allergen challenge as a single intravenous dose does not attenuate early or late asthmatic responses to allergen in asthmatic subjects.  相似文献   
56.
目的定量观察雌激素刺激后内膜癌细胞的焦点粘连激酶(Focal—adhesion kinase,FAK)转录水平。方法不同浓度的17β-雌二醇体外刺激雌激素敏感的内膜癌细胞株RL95—2。加用三苯氧胺或ICI 182,780雌激素拮抗剂的细胞及未加雌激素的细胞设为阴性对照。经不同作用时间后,采用实时RT—PCR方法测定处理后的细胞内FAK的mRNA水平。结果在给予不同浓度的雌激素共培养1d或5d后,细胞的FAK基因的转录水平对比阴性对照细胞无明显改变。结论雌激素对内膜癌细胞的FAK转录可能无显著影响。FAK基因在内膜癌组织中的过度表达的机理需要进一步深入研究。  相似文献   
57.
目的:检测粘着斑激酶(FAK)和血管内皮生长因子(VEGF)在直肠癌中的表达及其与侵袭和转移的关系,探讨二者的相关性。方法:采用免疫组织化学SABC法,观察86例直肠癌及30例非直肠癌组织中FAK和VEGF的表达情况。结果:FAKVEGF在直肠癌中的阳性率分别为80%和59%。在非直肠癌组织中的阳性表达率分别为10%和13%。FAKF和VEGF在侵及浆膜层直肠癌病例中的表达明显高于未侵五2浆膜层者,二者之间差异性有统计学意义(P〈0.05);有淋巴结转移组与无淋巴结转移组比较差异有统计学意义(P〈0.05),FAK与VEGF阳性表达呈正相关(p〈0.01)。结论:FAK、VEGF在直肠癌的侵袭和转移中起重要作用,二者在直肠癌中表达升高可以作为预测直肠癌侵袭和转移的指标  相似文献   
58.
目的研究不同压强持续性CO2气腹处理对结肠癌细胞侵袭能力的影响。方法建立体外气腹模型,选用人结肠癌细胞株SW1116,分别在不同压强(6、9、12及15mmHg)99.5%医用CO2气体以及常规培养条件下暴露1h,取各压强组处理后0h和72h细胞,使用体外细胞侵袭实验模型进行体外侵袭实验。结果气腹处理后即刻(0h),15mmHg压强组结肠癌细胞侵袭荧光强度(11.36±0.861)明显低于处理前(13.43±1.113),差异有统计学意义(P=0.019),且明显低于其他各组(6mmHg组:15.58±1.015,P=0.000;9mmHg组:13.49±0.750,P=0.011;12mmHg组:13.37±0.949,P=0.016;常规培养组:13.43±2.027,P=0.014);6mmHg压强组处理后细胞侵袭荧光强度(15.58±1.015)高于处理前(14.42±1.491),但差异尚未达到统计学意义(P=0.056),且显著高于其他各压强组(9mmHg组:P=0.013;12mmHg组:P=0.009;15mmHg组:P=0.000;常规培养组:P=0.011)。气腹处理后72h,各压强组处理前、后的结肠癌细胞侵袭荧光强度差异无统计学意义(P>0.05);处理后各压强组间的结肠癌细胞侵袭荧光强度差异亦无统计学意义(P>0.05)。结论CO2气腹能对结肠癌细胞的侵袭能力产生一过性影响,随着CO2气腹压强的增高,结肠癌细胞的侵袭能力可能受到抑制。  相似文献   
59.
目的探讨左旋聚乳酸/聚磷酸钙纤维(PLLA/CPPf)与同种异体的脱钙骨基质(DBM)对BMSCs黏附作用的差异,为构建组织工程骨提供理想的支架材料。方法用扫描电镜观察两种支架材料的孔径;通过测吸水率比较其亲水性。将普通培养瓶培养的第3代BMSCs分别成骨诱导培养1周后,在体外分别与PLLA/CPPf和同种异体的DBM复合构建组织工程骨,于构建后10h计算细胞黏附率,并用扫描电镜观察比较两种支架材料对BMSCs黏附作用的差异。构建后每天在相差显微镜下观察BMSCs在两种支架材料上的生长情况,构建后第10天再行扫描电镜观察BMSCs在两种支架材料上的生长情况。结果DBM的孔径明显较PLLA/CPPf的大,孔隙率高,体外构建后10hDBM组的细胞黏附率为(91.3±8.2)%,PLLA/CPPf组为(82.2±7.7)%,两者之间差异具有统计学意义(P〈0.05)。DBM组于术后第3天网孔间出现细胞外基质,且随着时间的推移,基质变得稠密,而PLLA/CPPf的细胞外基质鲜见;第10天的扫描电镜也证实DBM组的细胞在支架材料上数量多,且细胞外的基质分泌较多。结论DBM较PLLA/CPPf更适于BMSCs的黏附生长,是理想的组织工程支架材料。  相似文献   
60.
Objective To investigate the prevention of intestines adhesion about sodium hyaluronic acid in postoperative intestines adhesion.Methods Eighteen cases of adhesive intestine obstruction were done intestinal release or bowel resection.2~4mL sodium hyaluronic acid was put to the wound,anastigmatic and rough surface of peritoneal.Gastrointestinal decompression,anti-infective and infusion were taken after oper-ations.Followed up 8~24 months.Results Obstructive symptoms haven't happened,the effective rate is 100%.Only 2 cases have intermittent abdominal pain without obstruction,the incidence was 11%.Conclu-sion Sodium hylauronic acid is effective to prevent the adhesion of postoperative intestines adhesion,simp-ler use,fewer side-effects and great value to appliance.  相似文献   
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