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Objective To study the protective effect of TMP(Tetramethylpyrazine) on LPS(Lipopolysaccharides)-induced inflammatory response of human type Ⅱ alveolar epithelial cells (HAECⅡ) and its corresponding mechanism.Methods HAECⅡ (A549 cells derived from human lung adenocarcinoma cells) were cultured in vitro.Inflammation model was established using A549 cells after LPS stimulation.TMP and FK866 (a specific inhibitor for pre-B cell colony-enhancing factor), were added to intervene respectively.Expression level of mRNA, inflammatory factors including tumor necrosis factor-α (TNF-α), interleukin-1β(IL-1β), interleukin-8 (IL-8) and PBEF(pre-B cell colony-enhancing factor) were detected by q-PCR and Western blot, respectively.The activation of NF-κB(Nuclear factor κB) was examined by Western blot to find the changes in phosphorylated P65 protein level in both nucleus and cytoplasm.Results Both the mRNA and protein level of TNF-α, IL-1β, IL-8 and PBEF in A549 cells were significantly higher after LPS stimulation than those in the control group(P<0.001).Meanwhile, the phosphorylation of P65 protein in the nucleus and cytoplas was higher(P<0.001).The expression of the aforementioned inflammatory factors and the phosphorylation of P65 protein were significantly lower after TMP inter-vention than those of LPS group(P<0.05).In comparison, after FK866 was added, the expression of TNF-α, IL-1β and IL-8 and the phosphorylation of P65 protein were also decreased(P<0.01).Conclusions TMP may be involved in the reduction of PBEF expression, which therefore inhibits NF-κB activation, antagonizes alveolar epithelial cell inflammatory response.
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Objective To investigate the effects of positive end-expiratory pressure (PEEP) on hemodynamics and intra-abdominal pressure in patients with acute respiratory distress syndrome (ARDS) with normal intra-abdominal pressure (IAP) and intra-abdominal hypertension (IAH) during mechanical ventilation under a incremental PEEP.Methods Eighteen ARDS patients with normal IAP or IAH treated in intensive care unit of Anhui Provincial Hospital were enrolled for study.At different PEEP levels (5,10,15,20 cmH2O),hemodynamic parameters including extravascular lung water index (EVLWI),intrathoracic blood volume index (ITBVI),stroke volume variation (SVV) and IAP were measured with PICCO technology.Results Compared with ARDS patients with normal IAP,the ARDS patients with IAH were characterized by:(1) EVLWI was decreasing under the increment of PEEP,but there was no significant difference between 15 cmH2O and 20 cmH2O (t =0.593,P =0.572).As PEEP was gradually escalated,EWLVI had no significant changes in patients with normal IAP.(2) SVV increased as PEEP was being titrated to higher level in both groups but in normal IAP group such effect was observed till PEEP above 10cmH2O (PEEP5 vs.PEEP10,t=0.326,P=0.752; PEEP,10 vs.PEEP 15,t=-20.032,P＜ 0.01).(3) There was no statistical difference in ITBVI between two groups at varied levels of PEEP.(4) PEEP could increase IAP levels and had much more profound effects on patients with IAH.Conclusions PEEP is a contributing factor changing IAP.It is necessary to take the level of PEEP into account as IAP variation is interpreted in patients under mechanical ventilation.Different PEEP levels can significantly affect the EVLWI in patients with IAH but not do not in ones with nomal IAP.