Effect of Resolvin D1 and E1 on Mucin Expression in Human Airway Epithelial Cells / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Mucin is an important component of mucus that performs the first line of defense against inhaled pathogens and particles, lubrication of organs, and protection of airway. It is hyper-secreted in inflammatory airway diseases and is associated with morbidity and mortality of the affected patients. Resolvin, an autacoid of a specific lipid structure, exhibits anti-inflammatory property against inflammatory airway diseases although its effects on mucin secretion by human airway epithelial cells have not yet been demonstrated. In this regard, we investigated the effects of Resolvin on lipopolysaccharide (LPS)-induced mucin expression in human airway epithelial cells. MATERIALS AND METHOD: In mucin-producing human NCI-H292 epithelial cells, the effects and brief signaling pathways of Resolvin D1 (RvD1) and Resolvin E1 (RvE1) on the LPS-induced MUC4, MUC5AC, and MUC5B expression were investigated using reverse transcription-polymerase chain reaction, enzyme-linked immunosorbent assay and Western blot analysis. RESULTS: RvD1 attenuated LPS-induced MUC4, MUC5AC, and MUC5B mRNA expression and protein production in human NCI-H292 cells while RvE1 did not. RvD1 significantly blocked LPS-induced activated phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) mitogen-activated protein kinase (MAPK) and p38 MAPK and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) while RvE1 did not. CONCLUSION: These results suggest that RvD1 attenuates LPS-induced MUC4, MUC5AC, and MUC5B expressions via ERK1/2 MAPK, p38 MAPK, and NF-κB signaling pathways in airway epithelial cells. Therefore, RvD1 may modulate the control of mucus-hypersecretion in inflammatory airway diseases.

The Availability of Bedside Ultrasonography in Confirming Endotracheal Tube Placement in the Emergency Department

PURPOSE: The goal of this study was to determine the suitability of ultrasonography for detecting endotracheal tube placement in the emergency department. METHODS: Emergency physicians examined patients immediately following intubation or after intubated patients were transferred. A linear ultrasound transducer was placed transversely on the cricothyroid membrane and suprasternal notch in order to check for the "comet head and tail sign"and "double ring sign", and a sagittal view of the neck was also obtained in order to look for the "bold parallel lines sign". Subsequently, simple thoracic sonography and color doppler sonography were used to check for the "lung sliding sign". The examiner evaluated whether the tube was placed in trachea, the esophagus, or the right main bronchus. The accuracy of ultrasonography was calculated, and the required time for ultrasonography was checked. RESULTS: One hundred ten patients were enrolled in the study. The endotracheal tube was placed in the trachea in 107 patients, in the esophagus in 2 patients, and in the right main bronchus in 1 patient. The sensitivity and specificity of ultrasonography were 100%. The bold parallel lines sign and lung sliding sign proved to be good indicators of endotracheal tube placement. The average required time for ultrasonography was 28.6+/-5.8 seconds. It was difficult to determine tube placement by thoracic ultrasonography in patients with pneumothorax, hemothorax, pleural effusion, or empyema. CONCLUSION: Ultrasonography is well suited for confirming endotracheal tube placement in the emergency department.