BACKGROUND: There are reports that exogenous pulmonary surfactant (PS)participating in acute asthma attacks in rats with asthma and has correlation with epidermal growth factor(EGF) and expression of EGFmRNA.OBJECTIVE: To observe the effect of PS on EGF and EGFmRNA in asthmatic rats.DESIGN: Controlled experimental study on experimental animals.SETTING: Respiratory departmentof a military medical university affiliated hospital.MATERIALS: The experiment was completed in Laboratory 2 of Experiment Animal Center; Immunohistochemistry Laboratory, Department of Pathology of Fourth Military Medical University of Chinese PLA from April 2004 to July 2004. Sixty male SD rats weighting 100 - 120 g were provided by the Experiment Animal Center of the Fourth Military Medical University of Chinese PLA. The animals were randomly divided into 3 groups, that is normal control group, asthma control group(asthma group) and PS treatment group (treatment group) with 20 rats in each group.METHODS: The models of asthmatic rats were established. 1mL of immunogen stock suspension and 1 mL trachitis vaccine were injected intraperitoneally into the rats in the asthma group and treatment group respectively, and the normal control group were treated with the same volume of saline. Two weeks after being allergic, 10 g/L oval bumin were given to the asthma group and treatment group. The normal control group was given saline ultrasonic nebulization for 20 minutes; the treatment group was performed atomizing inhalation PS 100 mg/kg driving by oxygen before each provocation. The expression of EGF was detected with immunohistochemistry and the expression of EGF mRNA was detected with reverse transcription-polymerase chain reaction (RT-PCR).MAIN OUTCOME MEASURES: The onset condition of the rats in each group and the comparison of the level of EGF and the expression of EGFmRNA in lung tissue of the bronchus.RUSULTS: There were 20 rats entered the result analysis in each group. Onset rate of asthma in asthma group [90% (18/20) ] was higher than that in the treatment group[5% ( 1/20) ] (x2 = 28.97, P ＜ 0.01 ). The image analysis of the EGF expression showed that the absorbance in the asthma group(9. 652 ± 1. 086) was higher than that in the normal control group (3. 267 ± 0. 986) ( t = 18. 552, P ＜ 0.01 ). The absorbance in the treatment group(4. 132 ± 1. 012) was similar to that in the control group( P ＞ 0.05);The electrophoresis bands of mRNA amplified products in each group showed that in the normal control group the expression was weak and it was strong in the asthma group. The expression in the treatment group was obviously weaker than that in the control group.CONCLUSION: Exogenous PS can reduce the onset of asthma and its mechanism might be related with inhibiting the synthesis and release of EGF.

Bronchoalveolar lavage (BAL) was performed in healthy subjects (n = 12) and patients with bronchial asthma (n = ll). Between two groups there were no significant differences in total cells and percentage of alveolar macrophages (AM), lymphocytes, ncutrophils, cosinophils in BAL fluids. When AM were cultured in vitro and stimulated with dermatophagoides farinae(DPF) antigen, the quantity of PGE released by AM was significantly increased in asthmatics. When asthmatics' AM were sensitized with specific IgE positive serum and stimulated with DPF, they released more PGE, PGF2a than that when specific IgE negative serum was used (P

Objective To explore the mechanisms of corticosteroids regulating costimulatroy molecules on dendritic cells from mouse asthma model, and the role of SP-A in the process. Methods Murine asthma model was established with ovalbumin(OVA) sensitization and challenge, and the model was confirmed by histological analysis of lung tissues. Rabbit antibody against mouse, immunohistochemical ABC method and glucose-DAB-nickel technique for staining and computer image analysis is used to check the expression of pulmonary surfactant A (SP-A) in three groups. FACS was also used to measure the expression of CD-80 on spleen derived dendritic cell from OVA-sensitized and challenged mice. Data was analysised with spss 10.0 software. Results Histological analysis of lung tissues was consistent with the characteristic of murine asthma model. The expression of SP-A in small trachea of asthma group was decreased vs. control group and dexamethasone group(P

BACKGROUNDTo observe and explore the effects and mechanisms of fibronectin (FN) on invasion of different types of lung cancers.

METHODSUsing tumor invasion models in vitro of plates coated with FN and Boyden chambers with FN filter, differences of adhesion and migration between small cell lung cancer cell line (054A) and adenocarcinoma cell line (A549) were investigated, and proliferative effects of FN on cells were examined. In the meantime the invasive capability changes were observed after cell suspensions were preincubated with anti-α5, anti-α3 and anti-β1 integrin antibodies, respectively.

RESULTSFN could improve the adhesion, migration and proliferation of A549 more markedly than that of 054A. The number of adhesive cells in A549 cell line changed from 34.7± 5.1 to 189.4±12.3 with time from 2h to 12h compared with that from 19.8±7.9 to 159.2±11.9 in 054A cell line (P < 0.05 or P < 0.01). A549 cell line had 142.7±5.9 migration cells while 054A cell line had 89.4±4.7 (P < 0.01). FN could improved the proliferation in A549 cell line from 0.250±0.019 to 0.754±0.025 (P < 0.01) in concentration-dependent way, but in 054A from 0.205±0.026 to 0.286±0.029. And these effects were mediated mainly by α3β1 and α5β1 receptors in A549, but α3β1 in 054A.

CONCLUSIONSLung cancers with different origins express so different types and extents of integrin receptors that effects of FN on tumors are various, which is one of important reasons of different invasive capability of lung cancers.

Objective To investigate the current status of prevalence, prevention and management of chronic obstructive pulmonary disease(COPD) in rural area in China. Methods A cross-sectional survey of COPD was conducted in Beijing city, Shanghai city, Guangdong province, Liaoning province,Tianjin city, Chongqing province and Shanxi province. A population-based cluster sample was randomly selected from each rural area. In the selected community,all residents at least 40 years old were recruited,and interviewed with a modified standardized questionnaire from the international burden of obstructive lung diseases (BOLD) study. All participants were tested with spirometry. Those with airflow limitation were performed on post-bronchedilator spirometry. The post-bronchedilator a ratio of forced expiratory volume in one second to forced vital capacity (FEV1/FVC) less than 70% was defined as the diagnostic criteria of COPD. Results (1) Data of 9434 participants was valid for analysis, with a valid response rate of 83. 6% ;the prevalence of COPD in rural was 8. 8% (830/9434), 12. 8% in male and 5.4% in female. (2)The percentage of smoking and the exposure to biomass smoke in rural was 43. 0% (4059/9434) and 83. 1% (7835/9434) respectively; cigarettes cessation rate was 17.5% ; only 12. 4% ( 502/4059 ) of smokers had received advice to quit smoking. (3) Among COPD patients, only 30. 0% (249/830) had ever been diagnosed as COPD, bronchitis, emphysema, or asthma, 2. 4% (20/830) had ever received spirometric tests, and 74. 5% were current smokers; only 7.9% (50/634)COPD patients in stage two or over had received regular drug treatment. Conclusion There was high prevalence and poor prevention and management for COPD in rural areas. Therefore, an enforced prevention and management for COPD are urgent.