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Background

The aim of the study was to investigate how the expression of adhesion molecules changes as neutrophils migrate from the circulation to the lung and if these changes differ between non-smoking subjects and smokers with and without COPD.

Methods

Non-smoking healthy subjects (n=22), smokers without (n=21) and with COPD (n=18) were included. Neutrophils from peripheral blood, sputum and bronchial biopsies were analysed for cell surface expression of adhesion molecules (CD11b, CD62L, CD162). Serum, sputum supernatant and BAL-fluid were analysed for soluble adhesion molecules (ICAM-1, -3, E-selectin, P-selectin, VCAM-1, PECAM-1).

Results

Expression of CD11b was increased on circulating neutrophils from smokers with COPD. It was also increased on sputum neutrophils in both smokers groups, but not in non-smokers, as compared to circulating neutrophils.Serum ICAM-1 was higher in the COPD group compared to the other two groups (p<0.05) and PECAM-1 was lower in smokers without COPD than in non-smoking controls and the COPD group (p<0.05). In BAL-fluid ICAM-1 was lower in the COPD group than in the other groups (p<0.05).

Conclusions

Thus, our data strongly support the involvement of a systemic component in COPD and demonstrate that in smokers neutrophils are activated to a greater extent at the point of transition from the circulation into the lungs than in non-smokers.  相似文献   
23.
肺炎链球菌(Streptococcus pneumoniae,SP)普遍定植于呼吸道,是人类重要的侵袭性病原菌之一,是社区获得性肺炎、中耳炎、脑膜炎、菌血症、鼻窦炎的主要病原菌。肺炎链球菌粘附和毒力因子A(pneumococcal adherence and virulence factor A,PavA)是肺炎链球菌早期感染和侵袭过程中关键的毒力因子。体外试验表明,缺失PavA的肺炎链球菌的突变株其粘附和侵入上皮细胞和内皮细胞的能力明显下降。作为一种保护性抗原,其诱导的细胞和体液免疫可以有效的抵抗肺炎链球菌的感染,是肺炎链球菌新一代疫苗的候选蛋白。但是,PavA在肺炎链球菌与人肺上皮细胞交互对话中作用机制的研究尚属空白,本文就肺炎链球菌粘附和毒力因子A得最新研究进展作一综述。  相似文献   
24.
目的:探讨胰岛素对糖尿病兔牙槽骨缺损修复治疗的效果,为糖尿病所致的牙周炎提供临床治疗的依据,方法:40只大耳白兔随机分为4组:A组制备健康兔的牙槽骨缺损;B组为胰岛素组,制备健康兔牙槽骨缺损后,用胰岛素治疗;C组为糖尿病组,制备糖尿病兔牙槽骨缺损;D组为糖尿病胰岛素治疗组,制备糖尿病兔牙槽骨缺损后,用胰岛素治疗。每组10只,缺损制备后4、8周各处死5只,对各组成骨情况进行组织学观察及测定。结果:组织学观察A、B、D组修复区可见大量新骨形成,以B组为显著;C组仅见少许成骨,多为纤维组织。新生骨面积比和成骨细胞数在4、8周时均为D组大于c组,B组大于A组,组间差异有统计学意义(P〈0.05)。证明应用胰岛素促进糖尿病兔缺损牙槽骨形成新骨的效果明显。结论:胰岛素能够促进糖尿病兔牙槽骨缺损的戍骨,为,临床上治疗糖尿病并发牙周炎提供一种新的手段。  相似文献   
25.
目的:观察无创正压通气(NIPPV)联合纤维支气管镜(FB)肺泡灌洗对老年急性加重期慢性阻塞性肺疾病(AECOPD)合并Ⅱ型呼吸衰竭患者肺功能及血气指标的影响,为临床治疗方案的选择提供依据。方法:选取82例于2017年1月~2019年1月间在我院住院治疗的老年AECOPD合并II型呼吸衰竭患者。根据治疗方法将患者分为观察组(NIPPV联合FB肺泡灌洗治疗,n=42)与对照组(单独NIPPV治疗,n=40)。观察两组患者的住院时间及抗菌药静脉滴注时间,并比较治疗前及治疗后两组患者的血气指标[pH值(pH)、氧分压(PaO_2)、二氧化碳分压(PaCO_2)、血氧饱和度(SaO_2)]、肺功能指标[一秒钟用力呼气容积(FEV1)、肺活量(FVC)、呼气峰值流速(PEF)]的变化情况。记录两组患者治疗过程中的并发症发生情况。结果:观察组住院时间及抗菌药物静脉滴注时间均明显短于对照组(P0.05)。治疗后,两组pH、PaO_2、SaO_2明显上升,而PaCO_2明显下降(P0.05),且与对照组比较,观察组的pH、PaO_2、SaO_2明显较高,而PaCO_2明显较低(P0.05)。治疗后,对照组FEV1、FVC、PEF无明显变化(P0.05),观察组FEV1、FVC、PEF均明显升高且高于对照组(P0.05)。两组患者不良反应发生率比较差异无统计学意义(P0.05)。结论:NIPPV联合FB肺泡灌洗治疗对老年AECOPD合并II型呼吸衰竭患者血气指标及肺功能均有较好的改善效果,能明显缩短患者的住院时间及抗菌药静脉滴注时间,且安全性良好。  相似文献   
26.
绝经后雌激素缺乏会引起牙槽骨质流失、重塑和炎症。丁香油酚是一种酚类化合物,在牙科应用广泛并具有抗炎特性。在本研究中,以卵巢切除的大鼠为模型,服用不同剂量丁香油酚(2mg·kg-1·d-1和4mg·kg-1·d-1)12周(卵巢切除组),研究丁香油酚在牙槽骨组织中的骨保护作用。使用ELISA法检测血清中骨代谢标记物和促炎细胞因子,使用高分辨率微型计算机断层摄影术(CT)扫描牙槽骨形态,并进行骨组织学分析(H&E染色)。研究结果表明,丁香油酚不会增加卵巢切除大鼠体重和延缓子宫萎缩。由丁香油酚处理的卵巢切除大鼠的骨代谢标志物和炎性细胞因子含量显著提高,特别是高剂量组。丁香油酚的处理显著减弱了牙槽骨的形态测量变化,改善了牙槽吸收功能和牙龈渗透。卵巢切除大鼠的牙槽骨由于丁香油酚处理得到改善,炎性细胞因子表达降低。本研究初步结论表明,丁香油酚可以防止卵巢切除动物实验性诱导的牙槽骨损失,具有抗炎作用,对牙槽骨组织具有保护作用。  相似文献   
27.
The chemokine receptor CXCR2 and its ligands are implicated in the progression of tumours and various inflammatory diseases. Activation of the CXCLs/CXCR2 axis activates multiple signalling pathways, including the PI3K, p38/ERK, and JAK pathways, and regulates cell survival and migration. The CXCLs/CXCR2 axis plays a vital role in the tumour microenvironment and in recruiting neutrophils to inflammatory sites. Extensive infiltration of neutrophils during chronic inflammation is one of the most important pathogenic factors in various inflammatory diseases. Chronic inflammation is considered to be closely correlated with initiation of cancer. In addition, immunosuppressive effects of myeloid-derived suppressor cells (MDSCs) against T cells attenuate the anti-tumour effects of T cells and promote tumour invasion and metastasis. Over the last several decades, many therapeutic strategies targeting CXCR2 have shown promising results and entered clinical trials. In this review, we focus on the features and functions of the CXCLs/CXCR2 axis and highlight its role in cancer and inflammatory diseases. We also discuss its potential use in targeted therapies.  相似文献   
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In the immunocompetent host, Mycobacterium avium is responsible for chronic localized pulmonary disease, which is characterized by the presence of increased numbers of activated T cells and macrophages in the lungs. M. avium organisms as well as sonic extracts of M. avium were found to act as chemoattractants for THP-1 cells as well as monocytes, monocyte-derived macrophages and alveolar macrophages obtained from normal human donors in an in vitro chemotaxis assay, where a significantly higher number of cells were found in wells containing M. avium compared to control wells. Proteolytic treatment of M. avium sonicate resulted in significant loss (50%) of chemotactic activity. Monoclonal antibodies against recombinant human monocyte chemoattractant protein-1 (MCP-1) were found to cross-react with a 34-kDa protein of M. avium sonicate on Western blot and inhibit M. avium sonicate-mediated chemotaxis of THP-1 cells (47%). These data suggest the presence of an 'MCP-1 like' molecule on M. avium. Recruitment of host immune regulatory cells to the site of infection by pathogens may be involved in generating a local immune response or may be a bacterial strategy for survival within the host by recruiting the cells that they infect, i.e. macrophages.  相似文献   
30.
We have earlier identified the presence of a 36 kDa Ca2+-dependent phospholipid-binding protein (PLBP) in guinea pig alveolar type II cells. PLBP has been suggested to act as a mediator in facilitating and regulating intracellular surfactant assembly and delivery to the plasma membrane of type II cells for secretion into alveolar space. It has been reported that cigarette smoke exposure (CSE) causes a decrease in the surfactant activity in bronchial washings. We have also reported earlier that mainstream (MS) and sidestream (SS) CSE causes desensitization of -adrenoreceptors in guinea pig alveolar type II cells. Since both Ca2+ and -adrenoreceptors are involved in surfactant secretion and PLBP is involved in surfactant delivery, it is important to know whether CSE causes any change in the PLBP level in alveolar type II cells. In the present study, we have demonstrated that MS and SS CSE causes a significant increase in the levels of PLBP in alveolar type II cells (107 and 150%, respectively) and in lung lavage (42 and 125%, respectively) in comparison to that in sham control (430 ng/mg protein in alveolar type II cells and 780 ng/mg protein in lung lavage). The mechanism by which smoke exposure causes an elevation in the levels of PLBP in alveolar type II cells and lung lavage remains to be investigated.  相似文献   
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