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BACKGROUND: The important pathological changes of acute respiratory distress syndrome (ARDS) is disruption of the lung alveolar-capillary membrane barrier and resultant pulmonary edema associated with a proteinaceous alveolar exudate. Bone marrow mesenchymal stem cells (BMSCs) are able to carry on dividing and renewing themselves, and can eventually develop into many other types of cells. This provides a new treatment for treating injury of lungs.OBJECTIVE: To investigate the prevention of endotoxin-induced acute lung injury in rabbit by BMSCs.DESIGN, TIME AND SETTING: The randomized controlled animal study was performed at the Central Laboratory of Tangdu Hospital from October 2007 to January 2008.MATERIALS: A total of 20 rabbits were used in this study. Two rabbits were utilized to culture BMSCs. Eighteen rabbits were randomly assigned to three groups, saline control group, acute lung injury group and cell transplantation group (n = 6). Endotoxin was purchased from Sigma, USA.METHODS: Rabbit BMSCs were isolated and cultured by the Ficoll method. At the third passage, BMSCs were harvested for use.In the acute lung injury and call transplantation groups, endotoxin was infused into the trachea to establish models of acute lung injury/ARDS. Thirty minutes following model establishment, 2 mL BMSC suspension (1 x 105) was infused into the right jugular vein in the cell transplantation group. An equal volume of saline was injected into the saline control and acute lung injury groups.MAIN OUTCOME MEASURES: Number of neutrophilic granulocyte, wet to dry weight ratio of lung tissue, protein content and pathological changes in lung tissue in bronchoalveolar lavage fluid were measured.RESULTS: The increase in wet to dry weight ratio indicated the existence of pulmonary edema. The increase in neutrophilic granulocyte number suggested severe inflammatory reaction. The increased protein content showed the damage to lung alveolar-capillary membrane barrier. Following 48 hours of transplantation, neutrophilic granulocyte number and protein content in bronchoalveolar lavage fluid was significantly decreased (P < 0.01), and wet to dry weight ratio was significantly increased (P < 0.01) in the acute lung injury group compared with the saline control group. Compared with the acute lung injury group,neutrophilic granulocyte number and protein content was significantly increased (P < 0.01), and wet to dry weight ratio was significantly diminished (P < 0.01) in bronchoalveolar lavage fluid in the call transplantation group. Hematoxylin-eosin staining suggested that pulmonary alveoli was normal in the saline control group, presented typical acute lung injury in the acute lung injury group, and the pathological changes were mild in the cell transplantation group.CONCLUSION: BMSC transplantation can significantly reduce endotoxin-induced acute lung injury.
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Aim To investigate the changes of plasticity and distribution in the lungs of asthmatic guinea pigs.Methods Guinea pigs were divided into asthma group and control group.Immunohistochemistry was used in this study to observe the changes of ERK1/2 and Elk phosphoryiation in the lungs of guinea pigs.Results There were significant changes in distribution of EPK1/2 and Elk in the lungs of asthma group.The positive cells were detected on the walls of respiratory bronchioles and alveolar ducts,especially on the smooth muscle layer and basement membrane.In addition,the numbers of positive cell were clearly increased in asthma group(P< 0.01). Conclusion There is close relationship between the EPK1/2 and Elk phosphoryiation and attack of asthma.It may be a reason for persistence and progress of asthma.
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Objective To evaluate the significance of fibreoptic bronchoscopy combined with percutaneous pneumocentesis in the diagnosis of peripheral pulmonary lesions.Methods 269 patients with peripheral pulmonary diseases were diagnosed with fibreoptic bronchoscopy biopsy combined with bronchial brush biopsy.In 89 out of the 269 patients no positive findings were obtained,because the lesions were located in the lung hilum,medial sphere or mesosphere,when X-ray guided fibreoptic bronchoscopy biopsy combined with bronchial brush biopsy were employed.In 77 out of the 89 patients positive fingings were still lacking,as their lesions were located in the mesosphere or peripheralzone,when X-ray guided percutaneous pneumocentesis biopsy was used.In 70 out of the 77 patients,positive fingings were lacking,as their lesions were just beneath the chest wall,when B-ultrasonography guided percutaneous automatic elastic biopsy was employed.Results 276 times of fibreoptic bronchoscopy biopsy combined with bronchial brush biopsy were performed in 269 patients,final diagnosis was obtained in 82 of them,with a diagnostic rate of 30.5%;94 times of X-ray guided fibreoptic bronchoscopy biopsy combined with bronchial brush biopsy were performed in 89 patients,and final diagnosis was obtained in 66 patients,with a diagnostic rate of 74.2%;85 times of X-ray guided percutaneous pneumocentesis biopsy were performed in 77 patients,final diagnosis was obtained in 52,with a diagnostic rate of 67.5%;79 times of B-ultrasonography guided percutaneous automatic elastic biopsy were performed in 70 patients,final diagnosis was obtained in 49,with a diagnostic rate of 70.0%.A final diagnosis was made in a total of 249 patients,with a diagnostic rate of 92.6% when 4 methods were used in combination.Conclusion Combined use of fibreoptic bronchoscopy with percutaneous pneumocentesis biopsy may remarkably raise the diagnostic rate in the patients with peripheral pulmonary diseases,and is worth to be recommended for general use in clinical work.
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Objective To investigate the pathological features of airway remodeling and evaluate interventional effects of nerve growth factor (NGF) on the expression of matrix metalloproteinase-9 (MMP-9), an important mediator of airway remodeling, in guinea pig asthma model. Methods Guinea pigs were randomly divided into the control group, asthma group, and antibody NGF intervention group (each group had 8 guinea pigs). In the asthma group the animals were sensitized by repeated exposure to aerosolized ovalbumin combined with Al(OH)_3. The thickness of the smooth muscle of intrapulmonary bronchi was measured by image analysis system. The expression of MMP-9 in bronchi and lung tissues were assayed with immunohistochemistry combined with the micro-image analysis system. The levels of MMP-9 mRNA in bronchi and lung tissues were determined by RT-PCR. Results After repeated allergen challenge, obvious infiltration of inflammatory cells and proliferation of goblet cells and smooth muscle were demonstrated in guinea pig bronchi. Expression levels of MMP-9 in the epithelial cells of bronchi were significantly higher in asthmatic animals than those of control group animals. Compared with asthmatic group, there was mild inflammation reaction, and decrease in collagen deposition and expression of MMP-9 in antibody NGF group animals, and they were not significantly higher than that in control group animals. Conclusions Repeated exposure of allergen induced airway inflammation and remodeling. MMP-9 plays an important role in airway remodeling. Antibody NGF intervention could inhibit airway remodeling through inhibition of the expression of MMP-9.