Inhibition of TAK1 aggravates airway inflammation by increasing RIPK1 activity and promoting macrophage death in a mouse model of toluene diisocyanate-induced asthma / 南方医科大学学报

OBJECTIVE@#To explore the effect of transforming growth factor-β (TGF-β)-activated kinase 1 (TAK1) on toluene diisocyanate (TDI)-induced allergic airway inflammation in mice.@*METHODS@#Thirty-two mice were randomly divided into AOO group, AOO+5Z-7-Oxozeaenol group, TDI group, and TDI+5Z-7-Oxozeaenol group. Another 32 mice were randomly divided into AOO group, TDI group, TDI +5Z-7-Oxozeaenol group, and TDI +5Z-7-Oxozeaenol + Necrostatin-1 group. TAK1 inhibitor (5Z-7-Oxozeaenol, 5 mg/kg) and/or RIPK1 inhibitor (Necrostatin-1, 5 mg/kg) were used before each challenge. Airway responsiveness, airway inflammation and airway remodeling were assessed after the treatments. We also examined the effect of TDI-human serum albumin (TDI-HSA) conjugate combined with TAK1 inhibitor on the viability of mouse mononuclear macrophages (RAW264.7) using CCK8 assay. The expressions of TAK1, mitogen-activated protein kinase (MAPK) and receptor interacting serine/threonine protease 1 (RIPK1) signal pathway in the treated cells were detected with Western blotting. The effects of RIPK1 inhibitor on the viability of RAW264.7 cells and airway inflammation of the mouse models of TDI-induced asthma were evaluated.@*RESULTS@#TAK1 inhibitor aggravated TDI-induced airway inflammation, airway hyper responsiveness and airway remodeling in the mouse models (P < 0.05). Treatment with TAK1 inhibitor significantly decreased the viability of RAW264.7 cells, which was further decreased by co-treatment with TDI-HSA (P < 0.05). TAK1 inhibitor significantly decreased the level of TAK1 phosphorylation and activation of MAPK signal pathway induced by TDI-HSA (P < 0.05). Co-treatment with TAK1 inhibitor and TDI-HSA obviously increased the level of RIPK1 phosphorylation and caused persistent activation of caspase 8 (P < 0.05). RIPK1 inhibitor significantly inhibited the reduction of cell viability caused by TAK1 inhibitor and TDI-HSA (P < 0.05) and alleviated the aggravation of airway inflammation induced by TAK1 inhibitors in TDI-induced mouse models (P < 0.05).@*CONCLUSION@#Inhibition of TAK1 aggravates TDI-induced airway inflammation and hyperresponsiveness and may increase the death of macrophages by enhancing the activity of RIPK1 and causing persistent activation of caspase 8.

Receptor for advanced glycation end products upregulates MUC5AC expression and promotes mucus overproduction in mice with toluene diisocyanate-induced asthma / 南方医科大学学报

<p><b>OBJECTIVE</b>To explore the role of the receptor for advanced glycation end products (RAGE) in regulating the expression of MUC5AC and mucus production in a mouse model of toluene diisocyanate (TDI)?induced asthma.</p><p><b>METHODS</b>BALB/c mice were randomly divided into control group, vehicle (AOO) group, TDI?induced asthma group and RAGE inhibitor (FPS?ZM1) group. PAS staining, Western blotting, and immunohistochemistry were used to analyze the changes in mucus production and MUC5AC expression in the airway of the mice, and the expression of p?ERK was detected with Western blotting. In vitro cultured human bronchial epithelial cell line 16HBE was transfected with lentiviral vector carrying short hairpin RNA targeting RAGE (shRNA?RAGE) and subsequently challenged with a TDI?human serum albumin (TDI-HSA) conjugate, and the changes in cellular MUC5AC mRNA expression as detected using RT-PCR; the protein expressions of ERK and p?ERK in the cells were examined with Western blotting. The effect of ERK inhibitor U0126 pretreatment on MUC5AC mRNA expression was also analyzed in the cells.</p><p><b>RESULTS</b>Compared with the control mice, TDI-induced asthmatic mice showed significantly higher rates of PAS positivity and increased MUC5AC and p?ERK expressions in the airway (P<0.05). Treatment with FPS?ZM1 significantly decreased PAS positivity and lowered MUC5AC and p?ERK expressions in the airway of the asthmatic mice (P<0.05). Exposure of 16HBE cells to TDI?HSA caused a significant increase in MUC5AC mRNA expression and p?ERK protein expression (P<0.05), while RAGE knockdown obviously suppressed TDI?HSA-induced upregulation of p-ERK and MUC5AC mRNA (P<0.05). Treatment with the ERK inhibitor U0126 also lowered TDI?HSA?induced up?regulation of MUC5AC mRNA in the cells (P<0.05).</p><p><b>CONCLUSION</b>RAGE signaling induces MUC5AC expression via extracellular signal-regulated kinase pathway to promote mucus overproduction in mice with TDI-induced asthma.</p>

Role of epidermal growth factor receptor in house dust mite-induced airway epithelial barrier dysfunction / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the role of epidermal growth factor receptor (EGFR) signaling pathway in bronchial epithelial actin stress fiber (F-actin) rearrangement induced by house dust mite (HDM).</p><p><b>METHODS</b>Normal human bronchial epithelial cells (16HBE) were stimulated with HDM with or without pretreatment with AG-1478, an EGFR inhibitor. The levels of phospho(p)-EGFR, F-actin, E-cadherin and β-catenin in the cell cultures were detected with Western blotting. The localizations of F-actin, E-cadherin and β-catenin in the bronchial epithelial cells were determined with immunofluorescence assay, and the transmembrane electrical resistance (TER) and FITC-dextran flux (FITC-DX) in the cells were measured to assess the barrier function of the bronchial epithelia.</p><p><b>RESULTS</b>HDM stimulation of the cells for 10 min resulted in significantly increased p-EGFR expression (P<0.05) without causing obvious changes in the expression of E-cadherin (P>0.05) or β-catenin (P>0.05). Immunofluorescence assay revealed delocalization of E-cadherin and β-catenin in HDM-treated 16HBE cells, shown by their diffusion from the cell membrane to the cytoplasm. In HDM-treated cells, the TER was significantly decreased to (70.00∓4.33)% and the FITC-DX was significantly increased to (115.98∓4.34)%; Inhibition of EGFR reversed the delocalization of E-cadherin and β-catenin, improved the TER to (90.00∓3.75)% and lowered the FITC-DX to (101.10∓2.10)%. HDM induced increased expression and rearrangement of F-actin, which was obviously inhibited by pretreatment of the cells with AG-1478 (P<0.05).</p><p><b>CONCLUSION</b>EGFR signaling pathway mediates HDM-induced F-actin rearrangement in human bronchial epithelial cells to contribute to epithelial barrier dysfunction.</p>

High fractional exhaled nitric oxide may predict response to inhaled corticosteroid therapy in patients with subacute cough / 南方医科大学学报

<p><b>OBJECTIVE</b>To evaluate fractional exhaled nitric oxide (FENO) level in patients with subacute cough and its value in predicting the patients' response to inhaled corticosteroids (ICS) treatment.</p><p><b>METHODS</b>A total of 100 patients with persistent cough lasting more than 3 weeks were enrolled, including 52 patients with subacute cough and 48 with chronic cough. FENO, spirometry, and responses to ICS therapy of the patients were evaluated.</p><p><b>RESULTS</b>The recruited patients had a median (inter-quartile ranges) FENO level of 19 ppb (12-30 ppb). Patients with chronic cough had a significantly higher median FENO level than those with subacute cough (20.5 vs 16 ppb; Z=-2.245, P=0.025). A FENO level ≥25 ppb was recorded in 15 (28.8%) patients with subacute cough, as compared with 20 (41.6%) in patients with chronic cough (χ(2)=1.801, P=0.179). With a FENO ≥25 ppb as the critical value to justify ICS treatment, 15 patients with subacute cough received ICS and 14 (93.3%) of them showed obvious relief of cough after 2 weeks of therapy, a response rate similar to that of 85.0% (17/20) in patients with chronic cough receiving the treatment (χ(2)=0.588, P=0.443). In patients with subacute cough, those with cough variant asthma (CVA) or eosinophilic bronchitis (EB) had a significantly higher median FENO level than those with postinfectious cough [(16 (11-31) ppb vs 11 (8-19) ppb, P<0.01]. In the etiological analysis, CVA or EB was identified in 23 (44.2%) of the patients with subacute cough, as compared 21 (43.8%) in patients with chronic cough (χ(2)=0.002, P=0.961).</p><p><b>CONCLUSION</b>FENO may be an important indicator for etiological diagnosis of subacute cough and for predicting the response to ICS treatment.</p>

25-hydroxyvitamin D3-induced increases of normal human airway epithelial cell permeability is not mediated by upregulated ZO-1 expression / 南方医科大学学报

<p><b>OBJECTIVE</b>To observe the effect of 25-hydroxyvitamin D3 on the permeability and ZO-1 expression in normal human airway epithelial cells.</p><p><b>METHODS</b>MTT assay was used to assess the viability of human airway epithelial cell line 16HBE following a 24-hour exposure to different concentrations of 25-hydroxy vitamin D3, and the transepithelial electrical resistance (TER) of the cell monolayer was measured using a Millicell-ERS voltohmmeter. Real-time quantitative RT-PCR was employed to determine the changes of ZO-1 mRNA expression in the cells following the exposures.</p><p><b>RESULTS</b>Exposure to 25-hydroxyvitamin D3 resulted in significantly increased permeability of 16HBE cells, but the exspression of ZO-1 showed no obvious changes. 25-hydroxyvitamin D3 at 4×10(-9) mol/L showed the strongest effect in increasing the permeability of cell monolayer.</p><p><b>CONCLUSION</b>25-hydroxyvitamin D3 increases the permeability of normal bronchial airway epithelial cell monolayer in vitro, but this effect is not mediated by upregulation of ZO-1 expression.</p>

Localization and expression of Slingshot-1L in peripheral eosinophils from patients with acute asthma exacerbation / 南方医科大学学报

<p><b>OBJECTIVE</b>Eosinophils play a pivotal role in asthmatic airway inflammation. We previously found a significantly high expression of Slingshot-1L (SSH-1L) in peripheral eosinophils in acute exacerbations of asthma. Objective To investigate the expression and localization patterns of SSH-1L in peripheral blood eosinophils of asthmatic patients and their changes after treatment with inhaled corticosteroids.</p><p><b>METHODS</b>We recruited 4 outpatients with acute exacerbations of asthma who received no previous corticosteroid treatment and 1 healthy volunteer. From all the subjects 30 ml peripheral venous blood samples were collected before and after a 3-month treatment with inhaled fluticasone. The eosinophils were isolated, purified and counted, and the expressions of SSH-1L in the eosinophils were examined by RT-PCR and Western blotting. The localization of SSH-1L phosphatases in the peripheral eosinophils was detected by immunofluorescence assay in one patient.</p><p><b>RESULTS</b>SSH-1L phosphatases distributed diffusely in the cytoplasm, especially dense near the membrane of the peripheral eosinophils. Glucocorticoids treatment resulted in a significant reduction in both the SSH-1L mRNA expression (0.7403∓0.1124 vs 0.4101∓0.0363, P=0.001) and SSH-1L protein expression (0.3410∓0.1337 vs 0.1543∓0.0551, P=0.039).</p><p><b>CONCLUSION</b>A high expression of SSH-1L in peripheral eosinophils in acute exacerbations of asthma may play a role in the activation and migration of eosinophils. The efficacy of inhaled corticosteroids in asthma control might be partly attributed to a down-regulated expression of SSH-1L.</p>

Investigation of the level of perceived control of asthma and the factors affecting such perception in South China / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the level of the patients perceived control of asthma (PCA) in South China and analyze the risk factors contributing to inadequate PCA.</p><p><b>METHODS</b>A total of 150 asthmatic out-patients consisting of 86 males and 64 females aged 19-65 (38.6∓11.7) years were enrolled in this investigation. The patients were asked to complete questionnaires of the demographic data, perceived control of asthma (PCAQ-6) scales, asthma control test (ACT) scales and Standard asthma-specific quality of life [AQLQ(S)] scale. The data of spirometric measurements, blood cell count and induced sputum cell count were also collected.</p><p><b>RESULTS</b>All the 150 asthmatic out-patients recruited completed the questionnaires and examinations. The PCAQ-6 scores ranged from 10 to 26 (18.75∓3.42) in these patients (18.6∓3.28 in male and 18.95∓3.6 in female patients), significantly lower than those reported in other countries (P<1). PCA was positively correlated to the level of asthma control (r(p)=0.377, P=0.000) and AQLQ(S) scores (r(p)=0.675, P=0.000). Multiple linear regression showed that PCA was positively correlated to FEV1% and blood neutrophil counts, and inversely to asthma duration.</p><p><b>CONCLUSION</b>The level of the PCA appears inadequate in South China. The PCA can affect the level of asthma control and asthma-specific quality of life. The factors contributing to inadequate PCA include primarily asthma duration, lung function and blood neutrophil counts.</p>

Effect of toluene diisocyanate on reactive oxygen species production and permeability of human bronchial epithelial cells in vitro / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effect of toluene diisocyanate (TDI) on the production of reactive oxygen species (ROS) and the permeability of human bronchial epithelial (HBE) cells.</p><p><b>METHODS</b>TDI-human serum albumin (TDI-HSA) conjugate was prepared using a modified Son's method. MTT assay was used to assess HBE cell viability after exposure to different concentrations of TDI-HSA. The level of intracellular ROS of HBE cells was detected by flow cytometry with an oxidation-sensitive fluorescent probe 2',7'-dichlorofluorescein diacetate (DCFH-DA) uploading, and the permeability of cell monolayer was assessed by detecting the transepithelial electrical resistance (TEER).</p><p><b>RESULTS</b>The exposure to 120 µg/ml TDI-HSA did not obviously affect the cell viability. Compared with the control group, the intracellular fluorescent intensity increased significantly in the cells exposed to 20, 60, and 100 µg/ml TDI-HSA (P<0.05). The intracellular ROS production increased significantly after 100 µg/ml TDI-HSA treatment (P<0.05), but the increment in ROS production was significantly suppressed by pretreatment of the cells with N-acetylcysteine (NAC) (P<0.05), which also enhanced the TEER decreased by TDI-HSA treatment (P<0.05).</p><p><b>CONCLUSIONS</b>TDI enhances the permeability of HBE cell monolayer partially through a ROS-mediated pathway, suggesting the importance of oxidative stress in TDI-induced pulmonary diseases.</p>

Hydrogen dioxide increases the expression of vascular endothelial growth factor in human bronchiolar epithelium cell via a PI3K-dependent pathway / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effect of hydrogen dioxide (H(2)O(2)) on the expression of vascular endothelial growth factor (VEGF) in human bronchiolar epithelial (HBE) cells.</p><p><b>METHODS</b>MTT assay was used to assess HBE cell viability after exposure to different concentrations of H(2)O(2). VEGF/beta-actin gene fragments were amplified simultaneously by RT-PCR from the total HBE cell RNA, and VEGF protein expression in the cells was detected using ELISA.</p><p><b>RESULTS</b>The exposure to 200 micromol/L H(2)O(2) did not obviously affected the cell viability. Compared with those in the control cell, VEGF165/beta-actin and VEGF189/beta-actin ratios were significantly increased in the cells after treatment with 50, 200, and 600 micromol/L H(2)O(2) (P<0.05). The protein expression of VEGF significantly increased after 50 micromol/L H(2)O(2) treatment (P<0.05), but significantly decreased with pretreatment with the PI3K inhibitor Ly294002 (P>0.05).</p><p><b>CONCLUSION</b>Oxidative stress increases the expression of VEGF via a PI3K-dependent pathway in human bronchiolar epithelial cells, which may play an important role in the onset and maintenance of chronic inflammation in asthma.</p>

Therapeutic effect of tiotropium bromide powder inhalation in patients with stable bronchiectasis / 南方医科大学学报

<p><b>OBJECTIVE</b>To observe the therapeutic effect of tiotropium bromide powder inhalation on stable bronchiectasis.</p><p><b>METHODS</b>Twenty-two patients with stable bronchiectasis received inhalation of totropium bromide powder at the daily dose of 18 microg, and on days 1 and 28, the patients were examined for forced expiratory volume in one second (FEVl), predicted value [FEVl(%)], forced expiratory volume (FEV), and FEVl/FVC. The symptom score and BODE index were also recorded.</p><p><b>RESULTS</b>After 1 month of inhalation therapy, the FEV1% of the patients showed a moderate increase but the increment was not statistically significant (t=-1.875, P>0.05); the symptom score and BODE index decreased significantly after the therapy (t=7.091, P<0.001; t=2.982, P<0.05).</p><p><b>CONCLUSION</b>Long-term inhalation of tiotropium bromide powder can improve the clinical symptoms and BODE index and enhance the exercise tolerance and quality of life of the patients with bronchiectasis.</p>

Dimethylsulfoxide-induced expression of thymic stromal lymphopoietin in human bronchial epithelial cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effect of dimethylsulfoxide on the expression of thymic stromal lymphopoietin (TSLP) in human bronchial epithelial cell (HBE).</p><p><b>METHODS</b>16HBE cells were incubated in the presence of dimethylsulfoxide at different concentrations, and the cell proliferation changes were observed. The expressions of TSLP mRNA and protein in the cells were detected by real-time quantitative PCR and ELISA, respectively.</p><p><b>RESULTS</b>Dimethylsulfoxide induced significantly increased TSLP mRNA expression in HBE cells (P<0.01) in a concentration-dependent manner. The level of TSLP protein in the supernatant was also increased after dimethylsulfoxide treatment, but high concentration of dimethylsulfoxide resulted in e inhibited cell proliferation.</p><p><b>CONCLUSION</b>Dimethylsulfoxide may affect the immunomodulatory function of HBE cells.</p>

Analysis of the clinical indications of asthma control test / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the clinical indications of asthma control test (ACT).</p><p><b>METHODS</b>A total of 120 asthmatic patients with a diagnosis in line with the American Thoracic Society criteria and treated for over a month were enrolled in this study. The patients were asked to complete a survey to assess their symptoms and asthma attacks, and ACT evaluation was conducted by physicians familiar with ACT evaluation. The patients were classified into two groups based on the pulmonary function test (positive for bronchodilator test and provocation test) or based on disease severity (mild and moderate-to-severe asthma groups). The effect of ACT evaluation was graded as good (no less than 4 item available for evaluation), fair (2-3 items available) and poor (no more than 1 item). To further analyze the ACT sensitivity in relation to different disease severity, 29 asthmatic patients with an initial diagnosis and BDT positivity were included, and the ACT score of the patients with mild, moderate and severe asthma based on FEV1% were compared.</p><p><b>RESULTS</b>In patients positive for bronchodilator test, good, fair and poor evaluation effects were found in 48, 15, and 5 cases, as compared to 10, 15, and 27 in those positive for provocation test, respectively, showing significant differences between the two groups (P < 0.001). In mild asthma group, good, fair and poor evaluation effects were found in 12, 15, and 18 cases, respectively, significantly different from those in moderate-to- severe asthma group (50, 21, and 4 cases, P < 0.001). ACT scores showed a positive correlation to FEV1% in 29 patients with positive BDT (r = 0.55, P = 0.003). ACT scores had no significant difference between mild and moderate asthma groups (P > 0.05), but showed significant differences between mild and severe groups (P = 0.009) and between moderate and severe groups (P = 0.008).</p><p><b>CONCLUSION</b>ACT is more suitable for evaluating patients positive for bronchodilator test or with moderate to severe asthma.</p>

Expression of high mobility group box-1 in the lung tissue and BALF of asthmatic mice and the influence of dexamethasone / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the expression of high mobility group box-1 (HMGB1) in the lung tissue and bronchoalveolar lavage fluid (BALF) of asthmatic mouse models and the influence of dexamethasone (DM).</p><p><b>METHODS</b>Eighteen female Balb/C mice were randomly divided PBS control group, OVA group and OVA/DM group, and asthmatic mouse models were established in the latter two groups. The airway responsiveness of the mice was assessed by whole-body plethysmography, and the cells in the BALF were counted and classified, with the supernatants of the BALF collected for detection of the level of HMGB1 by ELISA. The left lung of the mice was collected for HE staining, and the expression of HMGB1 in the right lung tissue was detected by Western blotting.</p><p><b>RESULTS</b>Asthmatic mouse models were successfully established. The level of HMGB1 in the BALF was significantly higher in OVA group than in the control group (6.31 ± 4.05 ng/ml vs 2.59 ± 0.73 ng/ml, P = 0.017), but no significant difference was found between OVA/DM group (3.39 ± 0.50 ng/ml) and OVA group (PP = 0.052). The expression of HMGB1 relative to tubulin was significantly higher in OVA group than in the control group (2.08 ± 0.87 vs 0.85 ± 0.30, P = 0.032), but similar between OVA/DM group (1.15 ± 0.48) and OVA group (PP = 0.133).</p><p><b>CONCLUSION</b>The expression of HMGB1 is obviously increased in the lung and BALF of asthmatic mice and DM produces no significant effect on HMGB1 expression, suggesting that HMGB1 may serve as a new therapeutic target for asthma treatment.</p>

Respiratory syncytial virus increases the expression and release of high mobility group Box-1 protein in the lung tissue of mice / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the expression and release of high mobility group Box-1 protein (HMGB1) in the lung tissue of mice with respiratory syncytial virus (RSV) infection.</p><p><b>METHODS</b>Eighteen mice were randomized into PBS control group, RSV group and RSV/ribavirin group. Seven days after RSV infection in the mice in the latter two groups, the bronchoalveolar lavage fluid (BALF) was collected for cell counting and classification, and the levels of IL-4, IFN-gamma and HMGB1 in the supernatants of the BALF were detected. The left lungs of the mice were harvested for pathological examination with HE staining, and the right lungs were taken for detecting the expression of HMGB1 by Western blotting.</p><p><b>RESULTS</b>RSV induced a TH1 inflammation in the lung tissue as shown by significantly increased IFN-gamma and decreased IL-4 levels in the BALF. The total BALF cells, neutrophils and macrophages in the RSV group were significantly higher than those in the control group (P<0.05), and the cell counts were significantly decreased by ribavirin treatment (P<0.05). HE staining showed neutrophil and lymphocyte infiltration in the lumen and submucous layer of the airway in RSV group. The level of HMGB1 in the BALF significantly increased in the RSV group as compared with that in the control group (P<0.05), but was lowered by ribavirin treatment (P<0.05). The expression of the HMGB1 in the lung tissue significantly increased in the RSV group in comparison with that in the control group (P<0.05), and was not significantly decreased by ribavirin treatment (P>0.05).</p><p><b>CONCLUSIONS</b>The increased expression and release of HMGB1 in the lung tissue of mice with RSV infection is probably involved in the development of RSV infection-related lung diseases.</p>

Causal analysis of initial misdiagnosis of pulmonary embolism / 南方医科大学学报

<p><b>OBJECTIVE</b>To analyze the causes of initial erroneous diagnosis of pulmonary embolism (PE) to improve the diagnostic efficiency.</p><p><b>METHODS</b>The clinical data of 63 patients with a definite diagnosis of PE were retrospectively analyzed. According to the initial diagnosis, the patients were divided into definite diagnosis group (Group A, 23 cases) and misdiagnosis group (group B, 40 cases). The risk factors, initial symptoms, time of definite diagnosis, Wells scores, revised Geneva scores, and findings in chest X-ray and ECGs after onset and before the definite diagnosis were compared between the two groups.</p><p><b>RESULTS</b>In group A, recent operations, malignancy, long-term bedridden state, PE history and deep vein thrombosis (DVT) symptom were more commonly seen than in group B, and the patients in group B were more likely to have hypertension, smoking, diabetes mellitus and lower limb varicose veins. The patients in group B had significantly lower Wells scores and revised Geneva scores than those in group A [2.50 (5.00) vs 6.00 (6.00), u=-3.296, P<0.001; 5.50 (4.75) vs 12.00 (9.00), u=-3.187, P<0.001, respectively]. In group B, chest examination in 22 of the 40 cases (55%) reported pulmonary infection, and among them, 15 were misdiagnosed as pneumonia. In groups A and B, SIQIIITIII/QIIITIII in ECG was found in 5 (21.7%) and 0 cases (0%), and normal ECG in 2 (8.7%) and 18 (45.0%) cases, respectively, showing significant difference between the two groups (P=0.010 and 0.003, respectively).</p><p><b>CONCLUSION</b>The initial misdiagnosis of PE results mainly from the low awareness of some of the PE risk factors on the part of the physicians, atypical clinical manifestations and excessive dependence on chest films and ECGs.</p>

Value of nitrite in exhaled breath condensate in estimating the severity of asthma / 南方医科大学学报

<p><b>OBJECTIVE</b>To explore the relationship between nitrite levels in the exhaled breath condensates (EBC) and the severity of asthma.</p><p><b>METHODS</b>Sixty asthmatic patients with exacerbation (including 23 with mild, 21 with moderate, and 16 with severe asthma) and 23 healthy nonsmokers were enrolled in this study. The lung function tests were performed and nitrite levels measured in the EBC by the spectrophotometry and nitric oxide assay kit in these subjects. The percentage of eosinophils was also measured in induced sputum by Wright staining.</p><p><b>RESULTS</b>The concentrations of nitrites in the EBC and the percentage of eosinophils in induced sputum in the asthmatic patients were significantly higher than those of the healthy subjects (P<0.01), and showed positive correlations to the disease severity. A significant positive correlation was found between nitrites in the EBC and percentage of eosinophils in induced sputum (r=0.706, P<0.01). The concentration of exhaled nitrites was inversely correlated to MEF50% (r=-0.806, P<0.01) and FEV1% (r=-0.724, P<0.01).</p><p><b>CONCLUSION</b>Nitrite level in the EBC may serve as useful indicators for estimating the severity of asthma.</p>

Influence of education level on self-evaluation and control of patients with bronchial asthma / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effect of education on self-evaluation and control level in patients with bronchial asthma.</p><p><b>METHODS</b>Seventy-five asthmatic patients with the initial diagnosis in line with the American Thoracic Society criteria, including 46 with junior high school education or below (group A) and 29 with senior high school education or above (group B), were asked to complete a survey to assess their symptoms and asthma attacks. Asthma control test (ACT) and peak expiratory flow rate (PEFR) evaluation were performed 8, 12 and 24 weeks after salmeterol/fluticasone therapy. Step-down treatment was administered according to GINA guidelines. The self-evaluation of the patients was assessed according to ACT score, physical signs and pulmonary function. An ACT score over 19 indicate well controlled condition. The effect of education on the self-evaluation and control level of bronchial asthma was assessed.</p><p><b>RESULTS</b>The two groups had similar basal level of pulmonary function (FEV1). Eight weeks after the therapy, 29 patients in group A had ACT score over 19, including 11 with high control level; in group B, 17 had ACT score over 19, of whom 4 showed high control level. There was no significant difference between the two groups in control levels and self-evaluation (P>0.05). At 12 weeks, 37 patients in group A had ACT score over 19, with 17 having high control level; 22 patients in group B had ACT score over 19, 4 showing high control level; the two groups were similar in the control levels (P>0.05) but showed significant difference in self-evaluation (P<0.05). At the time of 24 weeks, 42 and 26 patients had ACT score over 19 in the two groups, with 19 and 5 having high control level, respectively. The two groups differed significantly in the control levels (P<0.05) and self-evaluation (P<0.05).</p><p><b>CONCLUSION</b>The patients' education level may play a role in self-evaluation and control level of bronchial asthma, but its impact differs in the course of the treatment.</p>

Effect of N-acetylcysteine on HMGB1 and RAGE expression in the lungs of asthmatic mice / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the expression of HMGB1 and RAGE mRNA in the lungs of asthmatic mice and the effect of N-acetylcysteine (NAC) on their expression.</p><p><b>METHODS</b>Twenty-one female BALB/c mice were randomly divided into control group, asthma group and NAC group (n=7). The expressions of HMGB1 and RAGE mRNA and their distributions in the lungs were detected by RT-PCR and immunohistochemical method.</p><p><b>RESULTS</b>The expression levels of HMGB1 and RAGE mRNA were not significantly different between the control group (0.88-/+0.02 and 1.20-/+0.20, respectively) and the asthma model group (0.86-/+0.05 and 1.21-/+0.08, P>0.05). After NAC treatment, both of HMGB1 and RAGE mRNA levels (0.98-/+0.05 and 1.58-/+0.21) were significantly higher than those in the other two groups (P<0.05). HMGB1 was found in the nuclei and membrane of the bronchial and alveolar epithelial cells, and RAGE was located on the membrane of the alveolar epithelial cells.</p><p><b>CONCLUSION</b>HMGB1 and RAGE may play a role in the oxidative stress during asthma, but the exact mechanism needs further investigation.</p>

Role of Smac in cisplatin-induced apoptosis of non-small cell lung cancer cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the role of Smac in cisplatin-induced apoptosis of non-small lung cancer cells in vitro.</p><p><b>METHODS</b>Non-small cell lung cancer A549 cells were incubated in the presence of cisplatin at different concentrations, and the cell proliferation status was observed using MTT assay. Flow cytometry was used for evaluation of the apoptosis of the incubated cells, and the expressions of Smac mRNA and protein were detected by RT-PCR and Western blotting, respectively.</p><p><b>RESULTS</b>Cisplatin inhibited the proliferation and induced apoptosis of A549 cells both in a concentration-dependent manner. Cisplatin also increased the expression of Smac at both the mRNA and protein levels, which was also concentration-dependent.</p><p><b>CONCLUSION</b>Increased Smac expression may play a critical role in cisplatin-induced apoptosis of the non-small cell lung cancer cells in vitro.</p>

Toluene diisocyanate increases vascular endothelial growth factor expression in human bronchial epithelial cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effect of toluene diisocyanate (TDI) on the expression of vascular endothelial growth factor (VEGF) in human bronchial epithelial (HBE) cells.</p><p><b>METHODS</b>TDI-human serum albumin (TDI- HSA) conjugate was prepared using a modified Son's method. MTT assay was used to examine the viability of HBE135-E6E7 cells cultured in serum-free medium after treatment with HSA or TDI-HSA at different concentrations. VEGF mRNA expression of the HBE cells treated with HSA or TDI-HSA at 10, 20, 30 and 40 microg/ ml, respectively, was detected using semi-quantitative RT-PCR.</p><p><b>RESULTS</b>Treatment with 40 microg/ml HSA and 40 microg/ml TDI-HSA did not result in significant changes in the viability of HBE135-E6E7 cells. RT-PCR revealed the constitutive expression of two VEGF isoforms, namely VEGF189 and VEGF165, in cultured HBE135-E6E7 cells. After exposure to TDI-HSA at the different concentrations (except for 10 microg/ml), a significant increase occurred in both VEGF189 and VEGF165 mRNA expressions in HBE135-E6E7 cells as compared with the expressions in the control group and the HSA-treated cells (P<0.05), and significant dose dependence was noted in the effect of TDI-HSA (P<0.05). No significant difference was found in the expressions between the control cells and the HAS-treated cells (P>0.05).</p><p><b>CONCLUSION</b>TDI induces significant increase in VEGF expression in HBE cells, and VEGF overexpression may play an important role in the pathogenesis of TDI-induced asthma.</p>