Degradation of bradykinin by bovine tracheal epithelium and isolated epithelial cells

1. The degradation of bradykinin (BK) labelled with tritiated proline at positions 2 and 3 ([³H]-BK) was determined on the luminal surface of bovine tracheal epithelium, in supernatants obtained from incubations of the luminal tracheal surface, and in suspensions of isolated tracheal epithelial cells. Peptidase inhibitors and identification of peptide fragments were used for characterization of the metabolic pathways.
2. On the luminal surface of intact bovine trachea, [³H]-BK was degraded with a half life of 12.8 min. [1-7]-BK and [1-5]-BK were the major direct metabolites which were further degraded via [1-3]-BK and [2-3]-BK to proline. Metabolism of [³H]-BK was unaltered in the presence of ramiprilat (250 nM) or phosphoramidon (10 μM). Phenanthroline diminished the formation of [1-7]- and [1-5]-BK and abolished the generation of proline.
3. Supernatants obtained from incubations of tracheal epithelium contained kininase activities which steadily increased when tracheae were incubated for longer than 30 min. After 60 min contact with epithelium, the incubation medium contained higher kininase activities than the epithelium itself. The spectrum of kinin metabolites generated by kininases in the supernatant was comparable to that formed by intact epithelium.
4. In suspensions of isolated epithelial cells, [³H]-BK was degraded with a half life of 70 min. The metabolites [1-3]- and [2-3]-BK were formed in parallel to [1-7]- and [1-5]-BK; however, proline was not generated. Degradation of [³H]-BK was not influenced by ramiprilat, but was inhibited by 85% in the presence of phosphoramidon. Phosporamidon markedly inhibited the generation of [1-7]- and [1-5]-BK and nearly abolished the formation of [1-3]- and [2-3]-BK.
5. In conclusion, angiotensin I-converting enzyme and neutral endopeptidase 24.11 are not significantly involved in [³H]-BK degradation on the luminal side of intact tracheal epithelium. The spectrum of metabolites found may in fact reflect the combined activities of metalloendopeptidase 24.15 and post-proline cleaving enzyme. Enzymes showing similar kininase activities are also released from the epithelium. Isolated epithelial cells contain low activities of these kininases, but a high activity of neutral endopeptidases, which may reflect an exclusively basolateral localization of the latter.

     

Allergen-antibody complexes can efficiently prevent seasonal rhinitis and asthma in grass pollen, hypersensitive patients

We have prepared antigen-antibody complexes from grass pollen allergens and autologous specific antibodies isolated by immunoadsorption from the serum of allergic patients. These complexes were inoculated into patients in a double-blind trial to evaluate their effect on grass pollen-related rhinitis and bronchial asthma. Thirty-eight grass pollen-hypersensitive patients were allocated to three groups; patients in the first two groups were treated with antigen-antibody complexes at different ratios and dosages and were compared with the third group who received the placebo carrier buffer alone. In addition, we treated a fourth group who had already received antigen-antibody complex inoculation during the previous pollen season. Injections were given every 2 weeks during the pollen season, starting 5 weeks prior to it. Tolerance was excellent with no signs of local or systemic side effects. The treatment prevented nasal symptoms while enabling the patients to reduce antihistamine intake. Bronchial asthma was virtually absent in the treated groups even though no bronchodilators or corticosteroids had to be taken. Specific IgE antibodies did not increase during the pollen season nor did IgG "blocking" antibodies. Inoculation of allergen-antibody complexes could provide a valuable alternative for the treatment of immediate hypersensitivity to airborne allergens as it appears to be safe and rapidly efficacious. This treatment offers several advantages compared to conventional hyposensitization and is characterized by the absence of an increase in specific IgG antibodies.     

沙丁胺醇联合异丙托溴铵治疗小儿哮喘55例

目的：观察沙丁胺醇和异丙托溴铵联合雾化吸入治疗儿童哮喘的疗效.方法：将儿童哮喘141例随机分为沙丁胺醇和异丙托溴铵联合雾化吸入组(A组)55例,单用沙丁胺醇雾化吸入组(B组)48例,单用异丙托溴铵雾化吸入组(C组)38例,分别治疗.沙丁胺醇雾化液与异丙托溴铵雾化液(用量均为0.25～1.00 mL)用0.9%氯化钠溶液稀释至2 mL,雾化吸入,每日2～4次.进行对照研究.结果：完全缓解率A组72.2%,B组45.8%,C组42.1%, A组的疗效明显优于B、C组(均P＜0.01).结论：联合应用沙丁胺醇和异丙托溴铵雾化吸入治疗儿童哮喘的疗效明显优于单用沙丁胺醇或单用异丙托溴铵.     

RFDD-PCR技术用于构建证的相关基因表达谱初探

目的　运用限制性酶切片段差异显示 (RFDD -PCR)技术初步筛选支气管哮喘肾虚证的相关基因 ,以冀探讨构建中医证的相关基因表达谱的一种研究方法。方法　应用RFDD -PCR技术 ,收集支气管哮喘肾虚证患者治疗前后外周血 ,分离其总RNA ,进行DNaseI处理、合成双链cDNA、TaqI限切酶酶切、在其两端连上接头、特异配对于接头的引物来降落PCR扩增、变性聚丙烯酰胺凝胶电泳、AgNO3 染色、回收差异条带并重新PCR扩增、反向斑点杂交、测序、生物信息学分析。结果　共找到 36条差异条带 ,其中 2 5条能用斑点杂交验证 ,选取 3条测序 ,结果与基因库比较未发现同源序列。结论　 3条基因片段可能是与支气管哮喘肾虚证相关的新基因 ;RFDD -PCR技术不失为构建中医证的相关基因表达谱的一种好方法。     

肺癌术后支气管切缘癌发生的相关因素分析

目的　探讨肺癌术后支气管切缘癌发生的相关因素。方法　对 2 43例原发性非小细胞肺癌患者的病例资料进行回顾性分析 ,采用Logistic回归分析判断术后支气管切缘癌发生的相关因素。 结果　 2 43例肺癌患者中 ,支气管切缘癌发生 3 1例 ,发生率为 12 .8% ,多因素分析显示 ,中央型肺癌、肺叶支气管淋巴结转移及组织学类型为鳞癌是支气管切缘癌发生的危险因素。结论　中央型肺癌、肺叶支气管淋巴结转移及组织学类型为鳞癌的肺癌病例应考虑发生术后支气管切缘癌的可能     

氯化镉诱发16HBE细胞系恶性转化过程中TIF3 p36的变化

目的 探讨氯化镉诱发人支气管上皮细胞（16HBE）恶性转化过程中不同阶段蛋白翻译起始因子（TIF3）p36 mRNA表达水平的变化,为进一步阐明氯化镉的分子致癌机制提供线索.方法 应用逆转录-聚合酶链式反应（RT-PCR）技术,以及敏感先进的Taqman荧光定量PCR方法,检测并分析氯化镉诱发16HBE恶性转化不同阶段即转化期间细胞、转化细胞和成瘤细胞的TIF3 p36 mRNA表达量的变化.结果 相对于非转化对照细胞（16HBE）,氯化镉诱发恶性转化不同阶段细胞（转化期间细胞、转化细胞和成瘤细胞）的TIF3 p36 mRNA基因表达水平均明显升高（P＜0.01或P＜0.05）,其中低剂量组（5 μmol/L）所转化的各阶段细胞的eIF3 p36 mRNA平均表达量分别是对照细胞的3.1、5.9和9.9倍,中剂量组（10 μmol/L）的各阶段转化细胞的TIF3平均表达量分别是对照细胞的7.1、6.8和14.8倍,高剂量组（15 μmol/L）的各阶段转化细胞的TIF3 p36平均表达量分别是对照细胞的3.6、3.0和9.1倍.这些不同剂量组的研究结果提示,eIF3 p36的异常表达量与氯化镉诱发16HBE细胞恶变程度之间有正相关关系,但与镉的剂量无关.结论 氯化镉在诱发16HBE细胞恶变过程中,存在明显的蛋白翻译启动因子eIF3 p36异常表达现象,其表达水平与细胞的恶变程度密切相关,这可能是氯化镉诱发人细胞肿瘤的重要分子致癌机制之一.     

致癌物诱导恶变细胞中线粒体高变区序列分析

目的检测苯并（a）芘代谢产物反式二羟环氧苯并芘（反式-BPDE）及结晶型硫化镍（NiS）诱发永生化人支气管上皮细胞系（16HBE）恶性转化过程中线粒体DNA控制区序列变化。探讨线粒体DNA控制区在环境致癌物苯并（a）芘及硫化镍致癌作用中是否存在靶分子序列。方法 应用银染PCR-单链构向多态性（SSCP）方法及测序方法分析恶变细胞中线粒体DNA高变区的序列变化。结果 经反式-BPDE和NiS诱导恶变的人支气管上皮细胞系线粒体高变区均未发现异常改变。结论 线粒体基因控制区可能并非是化学致癌物诱发肺癌的靶序列。     

小儿支气管哮喘与HLA的相关性研究

目的探讨小儿支气管哮喘与HLA-DRB1的相关件。方法采用序列特异性引物．聚合酶链反应方法（PCR／SSP）对78例支气管哮喘患儿和82例健康儿章进行HLA-DRB1基因分析，患儿的年龄为1～14岁，平均6．5岁。HLA-DRB。有19个等位基因，包括DR1-DRw18、DRw52和DRw53。计算各个位点的基因分布频率、危险性比值比OR值；并进行卡方检验，筛选有意义基因。结果支气管哮喘患儿HLA-DRB1^＊9的基因频率为10．8％；HLA-DRB1^＊10为11．5％；HLA-DRB1^＊1为1．92％。以上3个基因型住疾病组与正常组之间进行卡方检验，x^2值分别为4．39、4．44、6．7，与正常对照组比较差异有显著性（P均〈0．05），其余16个位点差异无显著性。观察组与对照组间进行逐个等位基凶比较，计算比值比OR结果HLA-DRB1^＊1的OR值为0．25；HLA—DRB1^＊9的OR值为2．58；HLA-DRB1^＊10的OR值为2．43。结论HLA-DRB1^＊9和HLA-DRB1^＊10可能是汉族小儿哮喘的易感基因；而HLA-DRB1^＊1可能为保护件基因。     

高渗盐水支气管激发试验

气道高反应性是哮喘的重要病理生理学特征，药物直接激发试验测定气道高反应性已被广泛应用，多年来在哮喘的诊断中发挥了重要作用。然而药物直接激发测定气道高反应性存在种种不尽人意的地方，近年来国内外有较多文献报道了高渗盐激发试验。为探讨高渗盐激发试验的应用价值，笔者对此作一综述。