急性呼吸窘迫综合征的药物治疗

急性呼吸窘迫综合征(acute respiratory distress syndrome,ARDS)的防治是多途径、综合性的救治过程.目前尚无治疗急性肺损伤(acute lung injury,ALI)/ARDS的特效药物,对其有缓解作用的药物主要针对其的急性渗出期、炎症反应或氧化损伤以及纤维增生期.联合多种药理因素...     

巨噬细胞LPS相关模式识别受体的研究进展

脓毒症(sepsis)是由各种致病微生物或其毒素引起的全身炎症反应综合征(systemic inflammatory response syndrome, SIRS),是严重感染、重度创伤、大手术后和休克常见的并发症,进一步发展可导致脓毒性休克、急性呼吸窘迫综合征(acute respiratory distress syndrome, ARDS)和多器官功能障碍综合征(multi-organ dysfunction syndrome,MODS)等致命性并发症.     

干细胞旁分泌效应在ALI/ARDS治疗中的研究进展

急性肺损伤(acute lung injury,ALI)以及它的严重形式——急性呼吸窘迫综合征(acute respiratorydistress syndrome,ARDS)是危重病人发病和死亡的重要原因之一,最近2个世纪以来,死亡率仍在36%～44%左右。ALI/ARDS的病因众多,发病机制十分复杂,涉及的环节多,受损的靶细胞多,主要涉及的环节有:炎症反应失控、细胞损伤与修复、细胞凋     

慢性酗酒与急性肺损伤/急性呼吸窘迫综合征

急性肺损伤/急性呼吸窘迫综合征(acute lung injury/accute respiratory distress syndrome,ALI/ARDS)是在非心源性疾病过程中.     

凝血和纤溶失衡在急性肺损伤中的作用

急性肺损伤(acute lung injury,ALI),以肺泡上皮细胞和血管内皮屏障损伤、急性炎症反应、富含蛋白的肺水肿为特征,是一种临床常见的危重病症,可进一步发展为急性呼吸窘迫综合症(acute respiratory distress syndrome,ARDS).     

肺血管内皮细胞分泌功能的改变与急性肺损伤/急性呼吸窘迫综合征

急性肺损伤(acute lung injury,ALI)/急性呼吸窘迫综合征(acute respiratory distress syndrome, ARDS)是临床上常见的急危重症,病死率高达25%~45%,治疗上主要限于器官功能与全身支持治疗,尤其是呼吸支持治疗,“等待”肺损伤的缓解。在ARDS发病机制中肺血管内皮细胞(pulmonary vascular endothelial cell,PVEC)既是受损的主要靶细胞,更是活跃的炎症和效应细胞,血管内皮细胞(vascular endothelial cell,VEC)的激活和损伤程度与ARDS预后密切相关。本文将主要阐述ALI/ARDS发病机制中PVEC部分分泌功能的改变。     

脓毒症中的细胞凋亡

脓毒症指机体对感染产生的全身性炎症反应的综合征,常发生于外伤、烧伤或免疫力低下时病原体严重感染,重者可发展为感染性休克、DIC和多器官功能衰竭等改变[1].脓毒症的发病机制与感染病原体、宿主免疫系统、炎症反应和凝血系统之间复杂的相互作用密切相关,其中全身炎症反应综合征(systemic inflammatory response syndrome,SIRS)、多器官损伤和感染性休克是常见的病理生理过程,但由于具体机制尚不明确,临床治疗效果不佳,死亡率一直居高不下[2,3].近年来研究显示细胞凋亡变化是脓毒症重要的病理变化之一[4].细胞凋亡(apoptosis)又称程序性细胞死亡,是机体形态发生、组织重塑和免疫反应消退过程中的一种主动性的死亡方式.与细胞坏死不同,凋亡的细胞或凋亡小体可被临近细胞所吞噬而不引起周围组织炎症反应.     

肠淋巴液在内毒素血症中的作用

内毒素血症是临床常见的多种急危重症并发症之一,发病机制复杂。许多革兰阴性菌感染的重症患者以及处于应激状态的患者,绝大部分会出现内毒素血症,而内毒素是格兰阴性菌细胞壁的脂多糖(Lipopolysaccharide,LPS)成分,LPS本身不会引起内毒素血症的血流动力学表现,但是与宿主免疫系统进一步相互作用后可以激发细胞因子的释放,严重时会引起内毒素休克,导致急性肺损伤(Acute lung injury,ALI),急性呼吸窘迫综合症(Acute respiratory distress syndrome,ARDS),全身炎症反应综合征(Systemic inflammatory response syndrome,SIRS)以及多器官功能障碍综合征(Multiple organ dysfunction syndrome,MODS)。近年来研究表明,肠淋巴管作为非细菌性、组织损害性、肠源性因素,已成为诱发呼吸窘迫综合症和多器官功能障碍的主要途径,本文就肠淋巴液在内毒素血症中的作用及其研究进展综述如下。     

NOD样受体蛋白3炎症小体在急性肺损伤/急性呼吸窘迫综合征中的作用机制研究进展

急性肺损伤/急性呼吸窘迫综合征(ALI/ARDS)是由多种非心源性肺内外因素引起的急性进行性呼吸衰竭,发病核心为过度放大或失控的炎症反应,目前没有特效的治疗药物.NOD样受体蛋白3(nucleotide-binding domain (NOD)-like receptor protein 3,NLRP3)炎症小体是细胞受到刺激时形成的多蛋白复合体,活化后导致细胞焦亡及IL-1β、IL-18等产生,在多种感染性、炎症性疾病中起重要作用.引起肺损伤的多种因素均可导致NLRP3炎症小体形成、活化,有研究提示,与ALI/ARDS中的过度炎症反应有关.因而深入研究NLRP3炎症小体在ALI/ARDS中的作用,对于进一步阐明ALI/ARDS的发病机制有重要意义,甚至有望成为治疗ALI/ARDS的新靶点.     

急性肺损伤/急性呼吸窘迫综合征与NF-κB信号转导关系的研究进展

急性肺损伤/急性呼吸窘迫综合征(ALI/ARDS)是临床上最常见的急危重症,其发病机制错综复杂,缺乏主动性治疗措施,病死率高。研究表明,核因子κB(NF-κB)为一种诱导型核转录因子,在ALI/ARDS发展过程中发挥极为广泛的功能,并与炎症反应具有密切的关系。现就ALI/ARDS、NF-κB信号转导通路及两者的关系作一简要的论述。     

全身炎症反应综合征-肺损伤大鼠肺组织IL-10mRNA表达及AP-1活性变化的研究

目的:复制脂多糖(LPS)致伤大鼠的全身炎症反应综合征(SIRS)-肺损伤模型,检测肺组织IL-10mRNA含量和AP-1活性的改变,探讨抗炎机制在SIRS-肺损伤中的作用。方法:梯级剂量LPS致伤Wistar大鼠,复制SIRS-肺损伤模型;逆转录PCR法(RT-PCR)检测大鼠肺组织IL-10mRNA含量;凝胶迁移率分析法(EMSA)检测大鼠肺组织激活蛋白-1(AP-1)活性。结果:①LPS致伤大鼠,可以模拟SIRS-肺损伤发生;②LPS≥6mg/kg可以导致ARDS形成,类似SIRS失控表现;③LPS可以导致大鼠肺组织IL-10mRNA含量和AP-1活性升高;④在非失控性演进为失控性SIRS-肺损伤过程中,当LPS≥6mg/kg时,大鼠肺组织IL-10mRNA含量和AP-1活性的升高幅度最大。结论:①LPS≥6mg/kg是大鼠SIRS-肺损伤发生失控的临界剂量;②大鼠SIRS-肺损伤失控伴有IL-10基因转录及其调控的异常增强;③抗炎机制增强参与了SIRS-肺损伤发生、发展的病理生理过程。     

CD44 as a novel target for treatment of staphylococcal enterotoxin B-induced acute inflammatory lung injury

Exposure to bacterial superantigens, such as staphylococcal enterotoxin B (SEB), can lead to the induction of acute lung injury/acute respiratory distress syndrome (ALI/ARDS). In the current study, we investigated the role of CD44 in ALI/ARDS. Intranasal exposure of CD44 wild-type mice to SEB led to a significant increase in the expression of CD44 on lung mononuclear cells. CD44 knockout mice developed significantly reduced SEB-induced ALI/ARDS, through reduced inflammatory cytokine production and reduced lung inflammatory cells, compared to similarly treated CD44 wild-type mice. Mechanistically, deletion of CD44 altered SEB-induced cytokine production in the lungs and reduced the ability of SEB-exposed leukocytes to bind to lung epithelial cells. Finally, treatment of SEB-exposed mice with anti-CD44 mAbs led to significant reduction in vascular permeability, reduction in cytokine production, and prevented inflammatory cell infiltration in the lungs. Together, these results suggest the possibility of targeting CD44 for the treatment of SEB-induced ALI/ARDS.     

Systemic Inflammation and Disseminated Intravascular Coagulation in Early Stage of ALI and ARDS: Role of Neutrophil and Endothelial Activation

To determine the existence of a close link between inflammation and coagulation in patients with acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) and to examine their prognostic value in the development of ARDS and clinical outcome, we made a prospective cohort study. The study subjects consisted of 57 patients: 19 patients with ARDS and 38 patients with ALI as defined by a Lung Injury Score of > or =2.5 and 1.0 to less than 2.5, respectively. According to the outcome, the patients were subdivided into the survivors and the nonsurvivors. Ten normal healthy volunteers served as control subjects. Plasma levels of soluble L-, P-, and E-selectins, intercellular adhesion molecule-1 (sICAM-1), vascular cell adhesion molecule-1 (sVCAM-1), thrombomodulin (sTM), and neutrophil elastase were measured within 24 h after the diagnosis of ALI or ARDS. The number of systemic inflammatory response syndrome (SIRS) criteria being met by the patients and the disseminated intravascular coagulation (DIC) scores were determined simultaneously. The number of SIRS criteria and the DIC scores of the patients with ALI or ARDS showed high values, and more than half of the patients were complicated by DIC. The levels of sL-selectin in both groups of the patients were significantly lower than those of the control subjects. All other soluble adhesion molecules, neutrophil elastase, and sTM in the patients with ALI and ARDS were markedly elevated than those in the control subjects. The levels sICAM-1, sVCAM-1, and sTM in the ARDS patients significantly increased compared with the ALI patients. The number of SIRS criteria and the DIC scores in the nonsurvivors showed higher values than those in the survivors. In addition, we found significant differences in the levels of soluble adhesion molecules, neutrophil elastase, and sTM between the survivors and the nonsurvivors. In conclusion, we found a concurrent activation of both inflammation and coagulation in the patients with ALI or ARDS. The results also suggest that systemic activation of inflammation and coagulation associated with endothelial injury has prognostic value for the development of ARDS and poor outcome.     

围急性呼吸窘迫综合征期循环中性粒细胞膜生物物理特性的改变

目的 :观察围急性呼吸窘迫综合征 (ARDS)期循环中性粒细胞(PMN)膜生物物理特性的改变 ,并分析这种改变在脏器炎性损伤发生中的意义。方法 :利用荧光染料染色扫描和阳离子染料染色比色法 ,分别测定正常人、系统性炎症反应综合征 (SIRS)、ARDS及多器官功能障碍综合征 (MODS)患者外周血PMN膜表面水化程度和负电荷量。结果 :SIRS阶段外周血PMN膜水化程度和负电荷量已明显下降 ,至ARDS期已降至低值 ,其后维持于低值。结论 :围ARDS患者外周血PMN明显降低的膜水化程度和膜电荷增加了PMN的相容性 ,使其更易于在肺血管床中附壁滞留 ,从而参与肺组织的炎性损伤过程。     

Effects of sivelestat on bronchial inflammatory responses after esophagectomy

Post-operative pulmonary complications such as systemic inflammatory response syndrome (SIRS), acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are strongly associated with morbidity and mortality after esophagectomy. Post-operative administration of sivelestat sodium hydrate (sivelestat), a selective inhibitor of neutrophil elastase (NE), has been shown to improve the post-operative clinical course after esophagectomy. This study aimed to evaluate the effect of prophylactic administration of sivelestat on bronchial inflammatory responses. We randomized 24 patients into two groups. One group received 0.2 mg/kg/h sivelestat from the induction of anesthesia to post-operative day 1 (sivelestat group) and the other group received the same amount of physiological saline (control group). Bronchial alveolar epithelial lining fluid (ELF) samples were obtained from both groups at the induction of anesthesia and at the end of surgery. The serum and ELF levels of interleukin (IL)-6 and IL-8 were measured by enzyme-linked immunosorbent assay, and NE activity was spectrophotometrically determined using the same samples. Although IL-6 levels in the ELF significantly increased at the end of surgery compared with the pre-operative levels in both groups, the IL-8 levels and NE activity did not significantly increase at the end of the surgery compared to the corresponding pre-operative values in the sivelestat group. Moreover, IL-8 levels and NE activity in the ELF were significantly reduced at the end of surgery in the sivelestat group compared with corresponding values in the control group. The durations of ALI and ARDS were apparently shorter in the sivelestat group and the duration of SIRS was significantly shorter in the sivelestat group compared to the control group. We demonstrated that prophylactic use of sivelestat mitigated bronchial inflammation by suppressing NE activity and IL-8 levels in the ELF and shortened the duration of SIRS after transthoracic esophagectomy.     

Role of inflammatory mediators in the pathophysiology of acute respiratory distress syndrome

Inflammatory response leading to organ dysfunction and failure continues to be the major problem after injury in many clinical conditions such as sepsis, severe burns, acute pancreatitis, haemorrhagic shock, and trauma. In general terms, systemic inflammatory response syndrome (SIRS) is an entirely normal response to injury. Systemic leukocyte activation, however, is a direct consequence of a SIRS and if excessive, can lead to distant organ damage and multiple organ dysfunction syndrome (MODS). When SIRS leads to MODS and organ failure, the mortality becomes high and can be more than 50%. Acute lung injury that clinically manifests as acute respiratory distress syndrome (ARDS) is a major component of MODS of various aetiologies. Inflammatory mediators play a key role in the pathogenesis of ARDS, which is the primary cause of death in these conditions. This review summarizes recent studies that demonstrate the critical role played by inflammatory mediators such as tumour necrosis factor (TNF)-alpha, interleukin (IL)-1beta, IL-6, platelet activating factor (PAF), IL-10, granulocyte macrophage-colony stimulating factor (GM-CSF), C5a, intercellular adhesion molecule (ICAM)-1, substance P, chemokines, VEGF, IGF-I, KGF, reactive oxygen species (ROS), and reactive nitrogen species (RNS) in the pathogenesis of ARDS. It is reasonable to speculate that elucidation of the key mediators in ARDS coupled with the discovery of specific inhibitors would make it possible to develop clinically effective anti-inflammatory therapy.     

IL-27 is Elevated in Acute Lung Injury and Mediates Inflammation

Cytokines play a critical role in the development of acute lung injury (ALI)/acute respiratory distress syndrome (ARDS). Here we investigated whether IL-27 was elevated in patients with ALI/ARDS and its potential clinical significance. Bronchoalveolar lavage (BAL) and serum samples were obtained from 58 ALI/ARDS patients, and 25 control healthy volunteers. IL-27 and other inflammatory mediators were measured in BAL and serum by ELISA. Besides, a mouse model of cecal ligation and puncture (CLP)-induced lung inflammation/injury was established, and serum, BAL fluid and tissues were collected for analyses in the presence or absence of IL-27 neutralizing antibodies. BAL IL-27 was found to be significantly higher in patients with ALI/ARDS than that in controls, particularly of pulmonary origin; serum IL-27 was also significantly higher. Increased IL-27 was associated with markers of inflammation, and correlated with disease severity of patients in ALI/ARDS. In a mouse model of CLP-induced lung inflammation/injury, elevated IL-27 levels were observed in the lung, serum, and BAL fluids. IL-27 neutralizing antibody treatment reduced pulmonary inflammation and lung injury and improved mouse survival in response to CLP. Therefore, IL-27 is a critical cytokine in ALI/ARDS and inhibition of IL-27 may open a promising approach for ALI/ARDS patients.