Regardless of whether a VT- or PL-NIV strategy is employed, it is possible to provide similar support to subjects with AHRF. (ClinicalTrials.gov registration NCT02538263.).

IL-33 played an important role in inflammatory diseases as evidenced by their high levels of expression in diseased tissues. Previous studies showed that IL-33/ST2L signal transduction pathway participated in epithelial-mesenchymal transition (EMT) of A549 cells. Cytokine IL-1β can increase the expression of MMPs by activating NF-kB. The excessive or inappropriate expression of MMP-9 may randomly and non-selectively destroy the extracellular matrix. TIMP-1 (tissue inhibitor of MMP-9) effects on ebb and flow of ECM by inhibiting activation of MMP-9. Therefore, IL-33 may take part in the process of pulmonary fibrosis by regulating expressions of MMP-9 and TIMP-1. To explore the acting mechanism of IL-33 in pulmonary fibrosis, proliferation of the human embryonic lung fibroblasts and expressions of related signal molecules was analyzed in vitro. We cultured HELF cells and stimulated HELF with rhIL-33 at different time points (24, 48, 72 h) and different concentrations respectively. The expression of the receptor ST2L was analyzed by RT-PCR and the proliferative rate of HELF was tested by MTT. The expressions of collagen IV, MMP-9, TIMP-1, and critical signal transducer TRAF-6 and NF-kappaB were tested by Western blotting. The rhIL-33 can promote proliferation of HELF and the concentration of 10 ng/ml was most significant at 72 h (P < 0.05). Hence, this experiment chose 10 ng/ml as stimulated concentration at following experiments. The expressions of collagen IV, MMP-9, TIMP-1, TRAF-6, and NF-kappaB increased and then reduced in protein levels at different time points (0, 6, 12, 24, 48, 72 h) (P < 0.05). IL-33 participates in the production of profibrotic cytokines and formation of mesenchymal substances in early inflammatory responses of pulmonary fibrosis. IL-33 can regulate deposition of ECM and promote the process of pulmonary fibrosis by inducing the imbalance between MMP-9 and TIMP-1.

Cough is a protective respiratory reflex used to clear respiratory airway mucus. For patients with cough weakness, such as chronic obstructive pulmonary disease, neuromuscular weakness disease and other respiratory diseases, assisted coughing techniques are essential to help them clear mucus. In this study, the Eulerian wall film model was applied to simulate the coughing clearance process through a computational fluid dynamics methodology. Airway generation 0 to generation 2 based on realistic geometry is considered in this study. To quantify cough effectiveness, cough efficiency was calculated. Moreover, simulations of four different coughing techniques applied for chronic obstructive pulmonary disease and neuromuscular weakness disease were conducted. The influences of mucus film thickness and mucus viscosity on cough efficiency were analyzed. From the simulation results, we found that with increasing mucus film thickness and decreasing mucus viscosity, cough efficiency improved accordingly. Assisted coughing technologies have little influence on the mucus clearance of chronic obstructive pulmonary disease models. Finally, it was observed that the cough efficiency of the mechanical insufflation-exsufflation technique (MIE) is more than 40 times the value of an unassisted coughing technique, which indicates that the MIE technology has a great effect on airway mucus clearance for neuromuscular weakness disease models.

To determine the effectiveness of neutrophil/lymphocyte ratio (NLR), compared to traditional inflammatory markers, for predicting noninvasive mechanical ventilation (NIMV) failure in acute exacerbation of chronic obstructive pulmonary disease (AECOPD) patients. Patients and Methods:We conducted this retrospective observational study including 212 AECOPD patients who required NIMV during hospitalization from January 2015 to December 2020 in the department of respiratory and critical care medicine of Beijing Chao-Yang Hospital (west campus). We reviewed the medical record to determine if NIMV succeeded or failed for each patient, and compared NLR with traditional markers (leukocyte, C-reactive protein [CRP] and procalcitonin [PCT]) between NIMV failure and NIMV success group. Receiver-operating characteristic (ROC) curve and multivariate logistic regression analysis were used to assess the accuracy of these markers for predicting NIMV failure. Results: A total of 38 (17.9%) patients experienced NIMV failure. NLR was a more sensitive biomarker to predict NIMV failure (AUC, 0.858; 95% CI 0.785-0.931) than leukocyte counts (AUC, 0.723; 95% CI 0.623-0.823), CRP (AUC, 0.670; 95% CI 0.567-0.773) and PCT (AUC, 0.719; 95% CI 0.615-0.823). There was statistically positive correlation between NLR and leukocytes count (r=0.35, p<0.001), between NLR and CRP (r=0.258, p<0.001), between NLR and PCT (r=0.306, p<0.001). The cutoff value of NLR to predict NIMV failure was 8.9 with sensitivity 0.688, specificity 0.886 and diagnostic accuracy 0.868. NLR>8.9 (odds ratio, 10.783; 95% CI, 2.069-56.194; P=0.05) was an independent predictor of NIMV failure in the multivariate logistic regression model. Conclusion: NLR may be an effective marker for predicting NIMV failure in AECOPD patients, and the patients with NLR>8.9 should be handled with caution since they are at higher risk of NIMV failure and require intubation. Further study with a larger sample size and with more data is necessary to confirm our study.

Sputum deposition blocks the airways of patients and leads to blood oxygen desaturation. Medical staff must periodically check the breathing state of intubated patients. This process increases staff workload. In this paper, we describe a system designed to acquire respiratory sounds from intubated subjects, extract the audio features, and classify these sounds to detect the presence of sputum. Our method uses 13 features extracted from the time-frequency spectrum of the respiratory sounds. To test our system, 220 respiratory sound samples were collected. Half of the samples were collected from patients with sputum present, and the remainder were collected from patients with no sputum present. Testing was performed based on ten-fold cross-validation. In the ten-fold cross-validation experiment, the logistic classifier identified breath sounds with sputum present with a sensitivity of 93.36% and a specificity of 93.36%. The feature extraction and classification methods are useful and reliable for sputum detection. This approach differs from waveform research and can provide a better visualization of sputum conditions. The proposed system can be used in the ICU to inform medical staff when sputum is present in a patient’s trachea.

Background/Aims Pigeon breeder’s lung (PBL) results from Th1/Th2 cell imbalance. B cells inhibit the immune activity of Th1, and EBF3 is a key B cell factor. This study explored the relationship between EBF3 and Th1/Th2 imbalance in chronic PBL cases complicated with pulmonary fibrosis (PF). Methods Twenty Uygur PBL+PF patients, 20 pigeon breeders without PBL or PF, and 20 healthy individuals without pigeon breeding history constituted the patient I, negative control, and normal control groups, respectively. Peripheral blood specimens and case backgrounds were collected between June 2016 and March 2017. EBF3 gene methylation was analyzed by matrix assisted laser desorption ionization-time of flight mass spectrometry. To compare different mechanisms of PF progression in PBL, samples from 20 Uygur PBL patients without PF (at acute and sub-acute stages) were collected between October 2017 and February 2018, constituting the patient II group. EBF3 mRNA expression was evaluated by real-time polymerase chain reaction. IFN-γ, IL-4 and IL-10 expression and Th1/Th2 imbalance in PBL were evaluated by enzyme-linked immunosorbent assay and flow cytometry. Results CpG-2 and general methylation rates in the patient I group were lower than those in the control groups (P˂0.017). The level of EBF3 mRNA expression in the patient I group was significantly higher than that in any other group. Compared with the control groups, the patient I group showed a significantly higher level of IL-4, whereas the patient II group showed a significantly lower level. IL-10 was also expressed more highly in the patient I group than in any other group (P< 0.01). Flow cytometry showed INF-γ dominance (Th1 cytokine) in PBL at the acute/sub-acute stage and IL-4 dominance (Th2 cytokine) at the chronic stage after PF occurred. The general methylation rate was negatively correlated with the mRNA level, with the latter being positively correlated with the IL-10 level and number of pigeons bred in the past 3 months. IL-4 expression was negatively correlated with INF-γ but positively correlated with PF area and duration of pigeon breeding history. Conclusions After PF occurs in chronic PBL, the inflammation type changes from Th1 dominance to Th2 dominance. During PBL development, IL-10 increases before IL-4 does, which may be associated with EBF3 hypomethylation and the involvement of B lymphocytes.

Background: To assess the usefulness of the neutrophil/lymphocyte ratio (NLR), a marker of inflammation and/or stress, for predicting weaning failure in patients receiving invasive mechanical ventilation (IMV), compared to levels of leukocytes and C-reactive protein (CRP). Methods: This observational prospective cohort study was conducted from July 2013 to December 2016 in an intensive care unit in China, enrolling 269 consecutive patients receiving IMV. Patients underwent a spontaneous breathing trial (SBT) if they were ready to wean, and underwent extubation if they passed the SBT. The evaluated markers were measured immediately prior to SBT, and compared between weaningfailure and weaning-success patients. Receiver-operating characteristic (ROC) curve and logistic regression analyses were used to evaluate the ability of these markers to predict weaning failure. Results: In all, 94 (34.9%) patients failed the weaning process (66 failed SBT and 28 presented with postextubation respiratory distress). NLR was a better predictor of failure (area under the ROC curve, 0.69; 95% CI, 0.62-0.76) than leukocyte levels (0.60, 0.53-0.67) and CRP values (0.58, 0.51-0.65). NLR >11, leukocyte counts >10.5×10 9 /L, and CRP >58 mg/L prior to weaning had the best combination of sensitivity (73%, 64%, and 63%, respectively), specificity (59%, 55%, and 63%), positive predictive value (49%, 43%, and 48%), negative predictive value (81%, 74%, and 76%), and diagnostic accuracy (64%, 58%, and 63%) for predicting weaning failure. However, only NLR >11 (odds ratio, 5.91; 95% CI, 3.08-11.33; P<0.001) was an independent predictor of weaning failure in the adjusted logistic regression model. Conclusions: NLR may be a useful marker for predicting weaning failure, and weaning at NLR >11 might be considered with caution. Further study with a larger sample size and with weaning outcome as a variable of concern is warranted. Trial registration: ClinicalTrials.gov identifier: NCT02981589.

COPD is characterized by a progressive decline in lung function and mental and physical comorbidities. It is a significant burden worldwide due to its growing prevalence, comorbidities, and mortality. Complication by bronchial-pulmonary infection causes 50%–90% of acute exacerbations of COPD (AECOPD), which may lead to the aggregation of COPD symptoms and the development of acute respiratory failure. Non-invasive or invasive ventilation (IV) is usually implemented to treat acute respiratory failure. However, ventilatory support (mainly IV) should be discarded as soon as possible to prevent the onset of time-dependent complications. To withdraw IV, an optimum timing has to be selected based on weaning assessment and spontaneous breathing trial or replacement of IV by non-IV at pulmonary infection control window. The former method is more suitable for patients with AECOPD without significant bronchial-pulmonary infection while the latter method is more suitable for patients with AECOPD with acute significant bronchial-pulmonary infection.