Lung injury could be classified as acute and chronic injuries, such as acute respiratory distress syndrome and chronic obstructive pulmonary disease. Lung function recovery mainly depends on inflammation adjusting, lung and airway remodeling, endogenous stem cell proliferation and differentiation, and tissue repair. The principles of clinical therapy include inhibition of inflammation, balancing coagulation and fibrinolysis, and protective lung ventilation for acute lung injury; while reduction of hyper-secretion, bronchodilation, adjusting airway mucosal inflammation and immunity, as well as improving airway remodeling for chronic obstructive pulmonary disease. The functional recovery of lung and airway depends on endogenous stem cell proliferation and repair. The purpose of clinical treatment is to provide assistance for lung and airway repair besides pathophysiological improvement.
ObjectiveTo observe the effects of aquaporin 1 (AQP1) on the proliferation and migration of endothelial progenitor-endothelial progenitor cells (EPC).MethodsBone marrow cells of AQP1 wild-type (WT) (n=6) and knockout-type (KO) mice (n=6) were isolated and differentiated into EPC in vitro. Immunofluorescence was used to detect cell surface antigens to identify EPC. Live cell kinetic imaging and quantification technology, transwell migration assays, as well as scratch test were used to compare the function of EPC between AQP1 WT and KO mice.ResultsEPC culture showed that cells were initially suspended and gradually adhered to typical mesenchymal stem cells within 7 days. After cultured on special medium for endothelial cells they were adhered and differentiated, and fusiform or polygonal, paving stone-like EPC were observed around 14 days. When cultured by special medium of EPC, CD133 and CD31 were positively detected after 7 days, and CD34 and Flk-1 were positively detected after 14 days. Positive expression of AQP1 was only detected in EPC of AQP1 WT mice. Functional studies of EPC revealed there was no significant difference in the proliferation of EPC between AQP1 WT and KO group mice. Transwell assay showed that EPC migration ability of AQP1 KO mice was significantly weaker than that of WT mice. The scratch healing ability of EPC in AQP1 KO mice was significantly lower than that of WT mice.ConclusionsEPC initially shows the characteristics of stem cells and with the prolongation of culture time, EPC gradually shows the characteristics of endothelial cells. AQP1 affects the EPC migration rather than proliferation.
ObjectiveTo investigate the relationship between platelets changes and outcomes of acute respiratory distress syndrome (ARDS) patients.MethodsA total of 275 ARDS patients treated in Zhongshan Hospital of Fudan University were retrospectively enrolled from 2008 to 2015. Their clinical characteristics, experimental test results and disease outcomes were obtained from the archived medical records. The correlation between the decreasing of platelet within three days and the prognosis of ARDS and in each subgroup were analyzed by statistical methods, including COX analysis and Kaplan-Meier curve.ResultsThere were 233 patients validly selected through eliminating those with exclusion criteria. They were divided into a decreasing group and a non-decreasing group according to their platelet counts in three days. There was significant difference in the ontcome between the two groups with the univariate analysis, the COX analysis and Kaplan-Meier curve (all P<0.05). According to the initial platelet count and change of platelet in 3 days all the patients were categorized into 9 subgroups. The mortality among them was compared and two risk groups were defined, including a persistently low platelet group (the initial platelet count <139×109/L with an increase less than 16×109/L during the first three days after the diagnosis), and a decreased platelet group (the initial platelet count ≥139×109/L and platelet count decreased more than 30×109/L during the first three days after the diagnosis). The other subgroups made up a non-risk group. Merging two risk groups as one risk group and comparing with the non-risk group, there were significant differences in the outcome between two groups with the univariate analysis, the multiplicity COX analysis and Kaplan-Meier curve (all P<0.05), the differences of coagulation function indexes were not significant (allP>0.05). The platelet count of the risk group was also an independent risk factor for ARDS mortality in the surgery subgroup (P=0.003), the non-hypertension subgroup (P=0.018) and the pneumonia subgroup (P<0.001).ConclusionLow platelets and declining platelets are closely associated with poor prognosis in most ARDS patients, which might be applied in clinical prognosis evaluation.