Idiopathic pulmonary fibrosis (IPF) is defined as a specific form of chronic, progressive fibrosing interstitial pneumonia. It is unknown why fibrosis in IPF distributes in the peripheral or named sub‐pleural area. Migration of pleural mesothelial cells (PMC) should contribute to sub‐pleural fibrosis. Calpain is known to be involved in cell migration, but the role of calpain in PMC migration has not been investigated. In this study, we found that PMCs migrated into lung parenchyma in patients with IPF. Then using Wt1 tm1(EGFP/Cre)Wtp /J knock‐in mice, we observed PMC migration into lung parenchyma in bleomycin‐induced pleural fibrosis models, and calpain inhibitor attenuated pulmonary fibrosis with prevention of PMC migration. In vitro studies revealed that bleomycin and transforming growth factor‐β1 increased calpain activity in PMCs, and activated calpain‐mediated focal adhesion (FA) turnover as well as cell migration, cell proliferation, and collagen‐I synthesis. Furthermore, we determined that calpain cleaved FA kinase in both C‐terminal and N‐terminal regions, which mediated FA turnover. Lastly, the data revealed that activated calpain was also involved in phosphorylation of cofilin‐1, and p‐cofilin‐1 induced PMC migration. Taken together, this study provides evidence that calpain mediates PMC migration into lung parenchyma to promote sub‐pleural fibrosis in IPF.

The distribution of fibrosis in idiopathic pulmonary fibrosis (IPF) is subpleural with basal predominance. Alveolar epithelial cell was considered as the key cell in the initial phase of IPF. However, the idea of activation and damage of alveolar epithelial cells is very difficult to explain why fibrosis distributes in the subpleural area. In this study, human pleural mesothelial cell (PMC) line and primary rat PMC was used as in vitro model. Intraperitoneal injection of bleomycin was used for making a pulmonary fibrosis model. The integrity of cultured monolayer PMCs was determined by transepithelial electric resistance (TEER). Pleural permeability was estimated by measuring paracellular transport of fluorescein isothiocyanate (FITC)-conjugated dextran. Changes in lung tissue of patients with IPF were analyzed by Masson's and immunofluorescence staining. We found bleomycin induced PMCs damage and increased PMCs permeability; increased PMCs permeability aggravated bleomycin-induced subpleural inflammation and pulmonary fibrosis. Moreover, bleomycin was found to activate VEGF/Src signaling which increased PMCs permeability. In vivo, inhibition of VEGF/Src signaling prevented bleomycin-induced subpleural pulmonary fibrosis. At last, activation of VEGF/Src signaling was confirmed in subpleural area in patients with IPF. Taken together, our findings indicate that VEGF/Src signaling mediated pleural barrier damage and increased permeability which contributes to subpleural pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a specific form of chronic, progressive and fibrosing interstitial pneumonia of unknown cause. The main feature of IPF is a heterogeneous appearance with areas of sub-pleural fibrosis. However, the mechanism of sub-pleural fibrosis was poorly understood. In this study, our in vivo study revealed that pleural mesothelial cells (PMCs) migrated into lung parenchyma and localized alongside lung fibroblasts in sub-pleural area in mouse pulmonary fibrosis. Our in vitro study displayed that cultured-PMCs-medium induced lung fibroblasts transforming into myofibroblast, cultured-fibroblasts-medium promoted mesothelial-mesenchymal transition of PMCs. Furthermore, these changes in lung fibroblasts and PMCs were prevented by blocking TGF-β1/Smad2/3 signaling with SB431542. TGF-β1 neutralized antibody attenuated bleomycin-induced pulmonary fibrosis. Similar to TGF-β1/Smad2/3 signaling, wnt/β-catenin signaling was also activated in the process of PMCs crosstalk with lung fibroblasts. Moreover, inhibition of CD147 attenuated cultured-PMCs-medium induced collagen-I synthesis in lung fibroblasts. Blocking CD147 signaling also prevented bleomycin-induced pulmonary fibrosis. Our data indicated that crosstalk between PMC and lung fibroblast contributed to sub-pleural pulmonary fibrosis. TGF-β1, Wnt/β-catenin and CD147 signaling was involved in the underling mechanism.

Idiopathic pulmonary fibrosis (IPF) is a fatal fibrosing interstitial lung disease with limited therapeutic options and a median survival of 3 years after diagnosis. Dysregulated epithelial regeneration is key event involved in initiating and sustaining IPF. The type II alveolar epithelial cells (AECIIs) play a crucial role for epithelial regeneration and stabilisation of alveoli. Loss of cell apical-basal polarity contributes to fibrosis. AECII has apical-basal polarity, but it is poorly understood whether AECII apical-basal polarity loss is involved in fibrosis. Bleomycin is a traditional inducer of pulmonary fibrosis. Here firstly we observed that bleomycin induced apical-basal polarity loss in cultured AECIIs. Next, cell polarity proteins lethal (2) giant larvae 1 (Lgl1), PAR-3A, aPKC and PAR-6B were investigated. We found bleomycin induced increases of Lgl1 protein and decreases of PAR-3A protein, and bleomycin-induced PAR-3A depression was mediated by increased-Lgl1. Then Lgl1 siRNA was transfected into AECIIs. Lgl1 siRNA prevented apical-basal polarity loss in bleomycin-treated AECIIs. At last, Lgl1-conditional knockout mice were applied in making animal models. Bleomycin induced pulmonary fibrosis, but this was attenuated in Lgl1-conditional knockout mice. Together, these data indicated that bleomycin mediated AECII apical-basal polarity loss which contributed to experimental pulmonary fibrosis. Inhibition of Lgl1 should be a potential therapeutic strategy for the disease.

PURPOSE:The aim of this study was to investigate the efficacy and safety of tratinterol hydrochloride in bronchial asthma (BA) treatment. METHODS:Patients enrolled in this study were distributed randomly into a treatment group (tratinterol hydrochloride) and an active control group (procaterol hydrochloride) and were treated for 2 weeks after running-in. The end points were changes in pulmonary function and clinical symptoms after administration. Safety indices were physical examinations, laboratory testing and spontaneous reporting. FINDINGS:We enrolled 732 subjects, -365 in the treatment group and 367 in the active control group. Forced expiratory volume (FEV1), significantly increased in both group after treatment (P < 0.05). Least-squares (LS) means were -0.03/in the full-analysis set (FAS) and -0.02 in the per-protocol set (PPS) set, and 95% confidence intervals (CIs) for these sets were -0.09 to 0.03 and -0.08 to 0.04, respectively. Forced expiratory volume (FVC), morning peak expiratory flow (PEF) and asthma scores were significantly different with pretreatment (P < 0.05). There was no difference in asymptomatic days or frequency of relief medicine use (P > 0.05). No serious adverse events occurred. IMPLICATIONS:Tratinterol hydrochloride was effective, safe and not inferior to procaterol hydrochloride in treating BA.

Idiopathic pulmonary fibrosis (IPF) is a chronic progressive lung disease that typically leads to respiratory failure and death. The cause of IPF is poorly understood. Although several environmental and occupational factors are considered as risk factors in IPF, cigarette smoking seems to be the most strongly associated risk factor. Here firstly, we treated mice with cigarette (16 mg tar, 1.0 mg nicotine in each cigarette) smoking and tried to explore the role of cigarette smoking in pulmonary fibrosis. Mice were continuously subjected to smoke for about 1 h each day (12 cigarettes per day, 5 days per week) during 40 days. Bleomycin was administrated by intraperitoneal injection at a dose of 40 mg/kg on days 1, 5, 8, 11 and 15. We found bleomycin induced pulmonary fibrosis in mice, and cigarette smoking augmented bleomycin-induced fibrosis reflected by both in fibrotic area and percentages of collagen in the lungs. Then we prepared and employed cigarette smoke extract (CSE) in cell models and found that CSE could induce the activation of p-Smad2/3 and p-Akt, as well as collagen-I synthesis and cell proliferation in lung fibroblasts and pleural mesothelial cells (PMCs). TGF-beta 1 signaling mediated CSE-induced PMCs migration. Moreover, in vitro studies revealed that CSE had superimposed effect on bleomycin-induced activation of TGF-beta-Smad2/3 and -Akt signaling. TGF-beta-Smad2/3 and -Akt signaling were further augmented by cigarette smoking in the lung of bleomycin-treated mice. Taken together, these findings represent the first evidence that cigarette smoking aggravated bleomycin-induced pulmonary fibrosis via TGF-beta 1 signaling.

Pleural fibrosis is associated with various inflammatory processes such as tuberculous pleurisy and bacterial empyema. There is currently no ideal therapeutic to attenuate pleural fibrosis. Some pro-fibrogenic mediators induce fibrosis through inflammatory processes, suggesting that blockage of these mediators might prevent pleural fibrosis. The MeT-5A human pleural mesothelial cell line (PMC) was used in this study as an in vitro model of fibrosis; and intra-pleural injection of bleomycin with carbon particles was used as an in vivo mouse model of pleural fibrosis. Calpain knockout mice, calpain inhibitor (calpeptin), and angiotensin (Ang) II type 1 receptor (AT1R) antagonist (losartan) were evaluated in prevention of experimental pleural fibrosis. We found that bleomycin and carbon particles induced calpain activation in cultured PMCs. This in vitro response was associated with increased collagen-I synthesis, and was blocked by calpain inhibitor or AT1R antagonist. Calpain genetic or treatment with calpeptin or losartan prevented pleural fibrosis in a mouse model induced by bleomycin and carbon particles. Our findings indicate that Ang II signaling and calpain activation induce collagen-I synthesis and contribute to fibrotic alterations in pleural fibrosis. Inhibition of Ang II and calpain might therefore be a novel strategy in treatment of pleural fibrosis.

Pleural fibrosis is barely reversible and the underlying mechanisms are poorly understood. Pleural mesothelial cells (PMCs) which have apical-basal polarity play a key role in pleural fibrosis. Loss of cell polarity is involved in the development of fibrotic diseases. Partition defective protein (PAR) complex is a key regulator of cell polarity. However, changes of PMC polarity and PAR complex in pleural fibrosis are still unknown. In this study, we observed that PMC polarity was lost in fibrotic pleura. Next we found increased Lethal (2) giant larvae (Lgl) bound with aPKC and PAR-6B competing against PAR-3A in PAR complex, which led to cell polarity loss. Then we demonstrated that Lgl1 siRNA prevented cell polarity loss in PMCs, and Lgl1 conditional knockout (ER-Cre+/-Lgl1flox/flox) attenuated pleural fibrosis in a mouse model. Our data indicated that Lgl1 regulates cell polarity of PMCs, inhibition of Lgl1 and maintenance of cell polarity in PMCs could be a potential therapeutic treatment approach for pleural fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a chronic progressive lung disease that typically leads to respiratory failure and death within 3-5 years of diagnosis. Sub-pleural pulmonary fibrosis is a pathological hallmark of IPF. Bleomycin treatment of mice is a an established pulmonary fibrosis model. We recently showed that bleomycin-induced epithelial-mesenchymal transition (EMT) contributes to pleural mesothelial cell (PMC) migration and sub-pleural pulmonary fibrosis. MicroRNA (miRNA) expression has recently been implicated in the pathogenesis of IPF. However, changes in miRNA expression in PMCs and sub-pleural fibrosis have not been reported. Using cultured PMCs and a pulmonary fibrosis animal model, we found that miR-18a-5p was reduced in PMCs treated with bleomycin and that downregulation of miR-18a5p contributed to EMT of PMCs. Furthermore, we determined that miR-18a-5p binds to the 3' UTR region of transforming growth factor beta receptor II (TGF-ORII) mRNA, and this is associated with reduced TGF-ORII expression and suppression of TGF-beta-Smad2/3 signaling. Overexpression of miR-18a-5p prevented bleomycin-induced EMT of PMC and inhibited bleomycin-induced sub-pleural fibrosis in mice. Taken together, our data indicate that downregulated miR-18a-5p mediates sub-pleural pulmonary fibrosis through upregulation of its target, TGF-beta RII, and that overexpression of miR-18a-5p might therefore provide a novel approach to the treatment of IPF.

Pleural fibrosis is defined as an excessive deposition of extracellular matrix (ECM) components that results in destruction of the normal pleural tissue architecture. It can result from diverse inflammatory conditions, especially tuberculous pleurisy. Pleural mesothelial cells (PMCs) play a pivotal role in pleural fibrosis. Calpain is a family of calcium-dependent endopeptidases, which plays an important role in ECM remodeling. However, the role of calpain in pleural fibrosis remains unknown. In the present study, we found that tuberculous pleural effusion (TPE) induced calpain activation in PMCs and that inhibition of calpain prevented TPE-induced collagen-I synthesis and cell proliferation of PMCs. Moreover, our data revealed that the levels of angiotensin (ANG)-converting enzyme (ACE) were significantly higher in pleural fluid of patients with TPE than those with malignant pleural effusion, and ACE-ANG II in TPE resulted in activation of calpain and subsequent triggering of the phosphatidylinositol 3-kinase (PI3K)/Akt/NF-κB signaling pathway in PMCs. Finally, calpain activation in PMCs and collagen depositions were confirmed in pleural biopsy specimens from patients with tuberculous pleurisy. Together, these studies demonstrated that calpain is activated by renin-angiotensin system in pleural fibrosis and mediates TPE-induced collagen-I synthesis and proliferation of PMCs via the PI3K/Akt/NF-κB signaling pathway. Calpain in PMCs might be a novel target for intervention in tuberculous pleural fibrosis.

目的 了解武汉市汉口社区慢性阻塞性肺疾病(COPD)患病情况、危险因素及疾病诊疗现状.方法 参考阻塞性肺疾病负担研究(BOLD)问卷制定调查表,以分层整群随机抽样方法,抽取武汉市汉口北湖及民意社区年龄≥40岁的常住居民进行调查,对所有入选者行问卷调查及肺功能检测,对肺功能检测确诊为COPD的患者,进一步行COPD综合评估.结果 共调查742例,689例资料完整,其中男性317例,女性372例,平均年龄(63.6±10.6)岁;COPD总患病率14.8％,其中男性为23.3％,女性为7.5％(P＜0.01).社区人群总吸烟率为43.6％,男性为82.0％,女性为11.0％.吸烟人群COPD患病率为24.5％,非吸烟人群患病率为7.2％(P＜0.01).COPD主要危险因素为年龄(OR=1.37,P＜0.01),吸烟(OR=3.02,P＜0.01),家族呼吸疾病史(OR=2.07,P＜0.05)及既往肺部疾病史(OR =4.21,P＜0.01).调查中诊断为COPD的患者,既往COPD诊断率为11.8％,肺功能检测率为23.5％,吸入药物使用率为35.3％.5.9％的COPD患者无任何临床症状.结论 武汉市汉口40岁以上社区居民COPD患病率高,年龄、吸烟、呼吸疾病家族史、既往肺部疾病史为危险因素,目前诊断率低、漏检率高并缺乏规范化吸入治疗.

Background. CD8+ T lymphocytes are known to play a critical role in the pathogenesis of chronic obstructive pulmonary disease (COPD). However, systematic analyses of CD8+ T cell (Cytotoxic T cells, Tc) subsets in COPD patients have yet to be well conducted. Methods. The whole Tc subsets, including Tc1/2/10/17, CD8+ regulatory T cells (Tregs) and CD8+α7+ T cells, were quantified by flow cytometry in peripheral blood from 24 stable COPD subjects (SCOPD), 14 patients during acute exacerbations (AECOPD), and 14 healthy nonsmokers (HN). Results. Acute exacerbations of COPD were accompanied by elevated levels of circulating CD8+ T cells. Tc1 cells were increased in both SCOPD and AECOPD patients, whereas the percentage of Tc2 cells was decreased in SCOPD patients but remained normal in AECOPD patients. Tc17 cells were increased only in AECOPD patients, and the percentage of Tc10 cells was reduced in both SCOPD and AECOPD patients. The imbalances of pro/anti-inflammatory Tc subsets observed in COPD may be caused by the lack of Tc10 cells and the impaired anti-inflammatory capacity of CD8+ Tregs. Conclusions. The imbalances between subsets of CD8+ peripheral blood T cells contribute to the immune response dysfunction in COPD pathogenesis.

Idiopathic pulmonary fibrosis (IPF) is a chronic progressive lung disease characterized by the development of subpleural foci of myofibroblasts that contribute to the exuberant fibrosis. Recent studies revealed that pleural mesothelial cells (PMCs) undergo epithelial-mesenchymal transition (EMT) and play a pivotal role in IPF. In animal model, bleomycin induces pulmonary fibrosis exhibiting subpleural fibrosis similar to what is seen in human IPF. It is not known yet whether bleomycin induces EMT in PMCs. In the present study, PMCs were cultured and treated with bleomycin. The protein levels of collagen-I, mesenchymal phenotypic markers (vimentin and α-smooth muscle actin), and epithelial phenotypic markers (cytokeratin-8 and E-cadherin) were measured by Western blot. PMC migration was evaluated using wound-healing assay of culture PMCs in vitro, and in vivo by monitoring the localization of PMC marker, calretinin, in the lung sections of bleomycin-induced lung fibrosis. The results showed that bleomycin induced increases in collagen-I synthesis in PMC. Bleomycin induced significant increases in mesenchymal phenotypic markers and decreases in epithelial phenotypic markers in PMC, and promoted PMC migration in vitro and in vivo. Moreover, TGF-β1-Smad2/3 signaling pathway involved in the EMT of PMC was demonstrated. Taken together, our results indicate that bleomycin induces characteristic changes of EMT in PMC and the latter contributes to subpleural fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a chronic progressive lung disease of unknown cause that typically leads to respiratory failure and death within 3-5years of diagnosis. TGF-β1 is considered a major profibrotic factor. However, TGF-β1 is necessary but not sufficient to the pathogenesis of fibrotic lesion of the lungs. Recent observations have revealed that calpain, a calcium dependent protease, plays a pivotal role in tissue remodeling and fibrosis. However, the mechanism of calpain mediating pulmonary fibrosis is not understood. Calpain conditional knockout (ER-Cre(+/-)capns1(flox/flox)) mice and primary human lung fibroblasts (HLFs) were used here to investigate the relationship between calpain and TGF-β1. Calpain knockout mice were protected from fibrotic effects of bleomycin. Bleomycin induced increases in TGF-β1 via calpain activation in HLFs. Moreover, TGF-β1 also activated calpain. This crosstalk between calpain activation and TGF-β1 triggered the downstream signaling pathway including TGF-β1 Smad2/3 and non-Smad (Akt) pathways, as well as collagen-I synthesis. Taken together, our data indicate that the crosstalk between calpain activation and TGF-β1 augments collagen-I synthesis in HLFs and in pulmonary fibrosis. Intervention in the crosstalk between calpain activation and TGF-β1 is a novel potential strategy to prevent pulmonary fibrosis.

BACKGROUND:Adrenomedullin (ADM) is a regulatory peptide with many biological actions, but little is known about its role in patients with COPD exacerbation. The purpose of this study was to evaluate the diagnostic and prognostic value of plasma ADM levels on hospital admission in patients with COPD exacerbation. METHODS:Consecutive subjects admitted to the hospital for COPD exacerbation were included and were followed up for 1 y; in addition, subjects with stable COPD from an out-patient clinic and healthy volunteers were recruited as controls. RESULTS:Compared with healthy subjects (145 pg/mL [interquartile range {IQR} 103-290 pg/mL]), plasma ADM levels were significantly higher in subjects with COPD exacerbation (270 pg/mL [IQR 170-510 pg/mL], P = .001) and in subjects with stable COPD (400 pg/mL [IQR 210-525 pg/mL], P < .001). In subjects with COPD exacerbation, ADM levels were significantly elevated during exacerbation (560 pg/mL [IQR 495-630 pg/mL]) compared with the recovery phase (470 pg/mL [IQR 393-553 pg/mL], P = .01) and the stable phase (200 pg/mL [IQR 143-308 pg/mL], P < .001). In receiver operating characteristic analysis, in subjects with COPD exacerbation, ADM had high diagnostic accuracy in differentiating between exacerbation and the stable phase (area under the curve 0.97, 95% CI 0.93-1.02, P < .001). In Cox regression analysis, plasma ADM was not independently associated with 1-y survival (P = .97), but it could accurately predicted the need for ICU care (hazard ratio 1.37, 95% CI 1.09-1.72, P = .008). CONCLUSIONS:Plasma ADM is a valuable biomarker to confirm COPD exacerbation; furthermore, plasma ADM independently predicts the need of ICU care, although it is not associated with long-term mortality in patients with COPD exacerbation.

Objective To investigate the mechanism of an inhibitor of NADPH oxidases,diphenylene iodonium (DPI),in preventing radiation-induced lung injury.Methods Totally 48 adult SD male rats were randomly classified into 4 groups:control group (C),radiation group (R),radiation plus DPI group (R + D) and DPI group (D).The radiation induced pulmonary injury model was preformed by using 6 MV X-rays to deliver 8 Gy per day for 5 consecutive days with 40 Gy in total to the thorax of each animal.Rats in R + D group were subcutaneously administered with 0.02％ DPI (1 mg/kg) at 1 h prior to radiation while rats in D group received the same dose of DPI without radiation.DPI was given from 3 d before radiation to 30 d after the first radiation.Rats in C and D groups received the same dose of saline.Animals were sacrificed at 1 month and 6 months after radiation,respectively.The lungs were removed and processed for HE and Masson staining,hydroxyproline content measurement,and TGF-β1 immunohistochemical detection.Results At 1 month post-radiation,rats in R group showed typical alveolitis,the level of hydroxyproline was (0.69 ± 0.05) μg/mg,and the positive area of TGF-β1 expression was (39.97 ± 0.90) ％,while the level of hydroxyproline in R + D group was (0.55 ± 0.03) μg/mg and the positive area of TGF-β1 expression was(33.83 ± 1.55) ％,rats in R + D group showed less severe alveolitis compared with R group(t =5.32,5.93,P ＜0.05).At 6 months post-radiation,rats in R group showed typical lung fibrosis with hydroxyproline level of (1.04 ±-0.02) μg/mg and TGF-β1 expression of (37.80 ± 0.85) ％,whereas the hydroxyproline level in R + D group was (0.85 ± 0.02) μg/ mg,the TGF-β1 expression was(23.93 ± 1.16)％,rats in R + D group showed moderate lung fibrosis(t =15.77,16.68,P ＜ 0.05),rats in C and D group had no noticeable changes.Conclusions Diphenylene iodonium could prevent radiation-induced lung injury by reducing the level of hydroxyproline and the expression of TGF-β1.

Background Chronic obstructive pulmonary disease (COPD) is characterized by chronic pulmonary and systematic inflammation. An abnormal adaptive immune response leads to an imbalance between pro- and anti-inflammatory processes. T-helper (Th), T-cytotoxic (Tc) and T-regulatory (Treg) cells may play important roles in immune and inflammatory responses. This study was conducted to clarify the changes and imbalance of cytokines and T lymphocyte subsets in patients with COPD, especially during acute exacerbations (AECOPD). Methods Twenty-three patients with stable COPD (SCOPD) and 21 patients with AECOPD were enrolled in the present study. In addition, 20 age-, sex- and weight-matched non-smoking healthy volunteers were included as controls. The serum levels of selected cytokines (TGF-β, IL-10, TNF-α, IL-17 and IL-9) were measured by enzyme-linked immunosorbent assay (ELISA) kits. Furthermore, the T lymphocyte subsets collected from peripheral blood samples were evaluated by flow cytometry after staining with anti-CD3-APC, anti-CD4-PerCP, anti-CD8- PerCP, anti-CD25-FITC and anti-FoxP3-PE monoclonal antibodies. Importantly, to remove the confounding effects of inflammatory factors, the authors introduced a concept of “inflammation adjustment” and corrected each measured value using representative inflammatory markers, such as TNF-α and IL-17. Results Unlike the other cytokines, serum TGF-β levels were considerably higher in patients with AECOPD relative to the control group regardless of adjustment. There were no significant differences in the percentages of either CD4+ or CD8+ T cells among the three groups. Although Tregs were relatively upregulated during acute exacerbations, their capacities of generation and differentiation were far from sufficient. Finally, the authors noted that the ratios of Treg/IL-17 were similar among groups. Conclusions These observations suggest that in patients with COPD, especially during acute exacerbations, both pro-inflammatory and anti-inflammatory reactions are strengthened, with the pro-inflammatory reactions dominating. Although the Treg/IL-17 ratios were normal, the regulatory T cells were still insufficient to suppress the accompanying increases in inflammation. All of these changes suggest a complicated mechanism of pro- and anti-inflammatory imbalance which needs to be further investigated.

Radiation leads to a rapid burst of reactive oxygen species (ROS), which is considered to be one of the major causes of radiation-induced injury. ROS have previously been shown to induce changes in cytosolic Ca²⁺ ([Ca²⁺]i) including [Ca²⁺]i oscillation. However, the role of radiation in [Ca²⁺]i oscillation is poorly understood. The purpose of this study was to identify the effect of ROS and X ray on [Ca²⁺]i oscillation, as well as their role in radiation-induced lung injury. Alveolar macrophages were cultured in the absence and presence of different doses of hydrogen peroxide (H₂O₂) or exposed to X-ray irradiation with or without pretreatment of diphenyleneiodonium chloride (DPI, an inhibitor of NADPH oxidases) or tetrandrine (TET, a calcium entry blocker) and cytosolic Ca²⁺ concentration was detected by fluorescent Ca²⁺ indicator Fura-2. Rat radiation lung injury was induced in vivo by using 40 Gy X ray and DPI or TET was used to prevent radiation-induced lung injury. The results showed that there was spontaneous [Ca²⁺]i oscillation in alveolar macrophages under normal conditions, and treatment of H₂O₂ (100-500 μM) or 2 Gy X ray inhibited the spontaneous [Ca²⁺]i oscillation and induced [Ca²⁺]i rise. TET abolished H₂O₂ or X ray induced [Ca²⁺]i rise in alveolar macrophages, and attenuated X ray- induced rat alveolitis in vivo. DPI prevented X-ray-induced inhibition of [Ca²⁺]i oscillation in alveolar macrophages and prevented X-ray-induced rat alveolitis. Taken together, the data suggest that the disruption of [Ca²⁺]i oscillation and induction of [Ca²⁺]i rise through ROS is involved in the mechanism of radiation-induced lung injury.

肺部浸润影在影像学上多表现为肺实质、肺间质阴影显著增多,可以为松散的云絮状或片状阴影,或者多发的线状影或点状影.在病因上分为感染性、非感染肺部浸润影.临床医生以病原学检查作为判断感染性或非感染性肺部浸润影的金标准,所以早期诊断困难,治疗滞后.

肺组织内浸入了异常细胞或出现了正常情况下不应出现的组织、细胞或其他物质或原有某些物质的堆积过多均可称之为肺浸润.在影像学上常表现为肺部阴影.肺浸润影往往是病理性的,提示肺组织出现了异常.引起肺浸润影的原因众多,大致可分为感染性和非感染性原因两大类[1].