Objective To investigate the effect of microRNA-22-3p (miR-22-3p) on the inflammation of human pulmonary microvascular endothelial cells (HPMEC) induced by lipopolysaccharide (LPS) by regulating the HMGB1/NLRP3 pathway. Methods miRNA microarray was taken from peripheral blood of patients with acute respiratory distress syndrome (ARDS) caused by abdominal infection and healthy controls for analysis, and the target miRNA was selected. miRNA mimics, inhibitor and their negative controls were transfected in HPMECs which were stimulated with LPS. Real time fluorescent quantitative polymerase chain reaction (RT-qPCR) and Western blot were used to detect the mRNA and protein levels of high mobility group box-1 protein (HMGB1) and nucleotide binding oligomerization segment like receptor family 3 (NLRP3). RT-qPCR and enzyme linked immunosorbent assay were used to detect the levels of inflammatory factors in the cells and supernatant. Results miRNA microarray showed that miR-22-3p was down-regulated in the plasma of patients with ARDS. Compared with the negative control group, after miR-22-3p over-expression, the protein and mRNA levels of HMGB1 and NLRP3 decreased significantly. Similarly, the level of cleaved-caspase-1 decreased significantly. At the same time, interleukin (IL)-6, IL-8 and IL-1β mRNA level in cytoplasm and supernatant were down-regulated by miR-22-3p mimics. After transfected with miR-22-3p inhibitor, the expression levels of HMGB1, NLRP3, caspase-1 protein and inflammatory factors were significantly up-regulated. Conclusion miR-22-3p is significantly downregulated in peripheral blood of ARDS patients caused by abdominal infection, which can inhibit the expression of HMGB1 and NLRP3 and its downstream inflammatory response in HPMECs.
Objective To observe the levels of von Willebrand factor ( vWF) expressed by human umbilical vein endothelial cells ( HUVECs) infected by aspergillus fumigatus ( AF) alone or treatment with cytochalasin D, N-cadherin monoclonal antibody, dexamethasone, respectively, so as to explore the mechanism of angioinvasion in invasive aspergillosis. Methods An in vitro model of HUVECs infected by AF hypha was established. The experiment included six groups, ie. a sham control group, a TNF-αgroup, an AF hypha group, a cytochalasin D group, a N-cadherin antibody group, and a dexamethasone group. Cell supernatants were collected to detect the levels of vWF at 2 h, 6 h, 12 h, and 18 h by enzyme linked immunosorbent assay ( ELISA) . Results Compared with that of vWF at 2 h, the level was higher at 18 h in the sham controlgroup and the TNF-αgroup, and higher at 6 h, 12 h, and 18 h in the other groups( P lt; 0. 05) . Compared with the sham control group, the level of vWF in each experiment group increased at 2 h, 6 h, 12 h, and 18 h except that in the N-cadherin antibody group at 2 h ( P lt; 0. 05) . The level of vWF in TNF-α group was higher than that in the AF hypha group at 2 h, but lower at 18 h. ( P lt; 0. 05) . The level of vWF was not significantly different between the cytochalasin D group and the AF hypha group at each time point. The level of vWF was lower in the N-cadherin antibody group than that in the AF hypha group at 2 h and 6 h ( P lt;0. 05) . The level of vWF was not significantly different between the dexamethasone group and the AF hypha group at each time point. Conclusion HUVECs infected by AF hypha overexpress vWF. N-cadherinmonoclonal antibody can reduce the expression of vWF, but cytochalasin D or dexamethasone has no significant effect on it.
Objective To study the advantages of heat and moisture exchangers compared with heated humidifiers in reducing the incidence of ventilator-associated pneumonia ( VAP) . Methods We searched PubMed as well as reference lists from publications to collect randomized controlled trials which comparing heat and moisture exchangers with heated humidifiers in preventing VAP for mechanically ventilated patients. Meta-analysis was performed using software Review Manager 5. 0. Results Fifteen randomized controlled trials were included. There was no difference in incidence of VAP among the patients managed with moisture exchangers or heated humidifiers ( OR1. 18, 95% CI [ 0. 96, 1. 44] ) . The subgroup of patients using moisture exchangers had lower VAP incidence compared with those using heated humidifiers without heated wire circuits ( OR 1. 39, 95% CI [ 1. 08, 1. 79] ) . There were no differences between the compared groups in mortality, length of intensive care unit stay, or duration of mechanical ventilation. Conclusion The available evidence indicates that moisture exchangers are superior to heated humidifiers without heated wire circuits, and not to heated humidifiers with heated wire circuits to prevent VAP.