Fluid dynamics of the upper airway in pediatric patients with severe laryngomalacia.

Laryngomalacia is the top cause of pediatric laryngeal wheeze. We used computational fluid dynamics to study the inspiratory airflow dynamics in severe pediatric laryngomalacia. Computed tomography was performed on the upper airways of two infants, one with severe laryngomalacia and one with normal airway, and 3D models were reconstructed. ANSYS CFD-POST software was used to simulate airflow in these models to compare the volumetric flow rate, flow velocity, pressure, wall shear, and vortex. The volume flow rate in the laryngomalacia model was significantly reduced compared with the control model. Under inspiratory pressures, the peak flow velocity, pressure, and shear force in the control model appeared at the soft palate stenosis, while that in the laryngomalacia model appeared at the supraglottis stenosis. In both models, the maximum flow velocity and shear force increased with decreasing inspiratory pressure, while the minimum pressure decreased with decreasing inspiratory pressure. In the control model, the airflow vortex appeared anteriorly below the posterior section of the soft palate. In the laryngomalacia model, the vortex appeared anteriorly below the posterior section of the soft palate and anteriorly below the vocal folds. Our methodology provides a new mechanistic understanding of pediatric laryngomalacia.

Epithelial-mesenchymal transition classification of circulating tumor cells predicts clinical outcomes in progressive nasopharyngeal carcinoma.

Background: Liquid biopsy facilitates the enrichment and isolation of circulating tumor cells (CTCs) in various human cancers, including nasopharyngeal carcinoma (NPC). Characterizing CTCs allows observation of the evolutionary process of single tumor cells undergoing blood-borne dissemination, such as epithelial-mesenchymal transition. However, the prognostic value of phenotypic classification of CTCs in predicting the clinical outcomes of NPC remains poorly understood. Patients and methods: A total of 92 patients who met the inclusion criteria were enrolled in the present study. The CanPatrol™ CTC technology platform was employed to isolate CTCs, and an RNA in situ hybridization-based system was used for phenotypic classification. Kaplan-Meier survival curves were used for univariate survival analysis, and the log-rank test was performed for between-group comparisons of the survival curves. Results: CTCs were detected in 88.0% (81/92) of the enrolled patients with NPC. The total CTC number did not vary between the T and N stages or between Epstein-Barr virus DNA-positive and -negative cases. The numbers of total CTCs and epithelial/mesenchymal (E/M) hybrid CTCs decreased significantly at 3 months post concurrent chemoradiotherapy (P=0.008 and P=0.023, respectively), whereas the numbers of epithelial or mesenchymal CTCs did not decrease. E/M hybrid-predominant cases had lower disease-free survival (P=0.043) and distant metastasis-free survival (P=0.046) rates than non-E/M hybrid-predominant cases. Conclusion: CTC classification enables a better understanding of the cellular phenotypic alterations responsible for locoregional invasion and distant metastasis in NPC. E/M hybrid-predominant CTC distribution predicts unfavorable clinical outcomes in patients with progressive NPC.

The effects of resiquimod in an ovalbumin-induced allergic rhinitis model.

Growing evidence indicates that the Toll-like receptor7/8(TLR7/8) agonist resiquimod (R848) is a potential inhibitor of type-2 immunity. However, the mechanisms mediating its therapeutic effects are not fully understood. This study investigated the effects of R848 on OVA-induced allergic rhinitis(AR) mice and the expression of IL-25, IL-33, TSLP, T-cell immunoglobulin mucin1 (TIM1) and T-cell immunoglobulin mucin3 (TIM3). BALB/c mice were intranasally sensitized and challenged with ovalbumin (OVA), and R848 was intraperitoneally injected into AR mice. Histological changes in the nasal mucosa were evaluated by hematoxylin and eosin (H & E) and Periodic Acid-Schiff (PAS) staining; cytokine levels in serum were measured with enzyme-linked immunosorbent assays (ELISAs);the mRNA expression levels of IFN-γ, IL-17 and Foxp3 in the spleen determined by quantitative real-time RT-PCR (qRT-PCR); the proportions of Th1, Th2, Th17, Treg and TIM3 + IFN-γ + Th1 cells in the spleen were assessed with flow cytometry; TIM1, TIM3 and IL-33 expression levels in the nasal mucosa were evaluated with immunofluorescence staining(IF).R848 alleviated the nasal allergic symptoms; reduced eosinophil cell infiltration, goblet cell hyperplasia in the nasal mucosa; reduced IL-13, IL-17, IL-25 and IL-33 levels in serum; upregulated the relative mRNA expression of IFN-γ and Foxp3, and downregulated the relative mRNA expression of IL-17 in the spleen; decreased Th2, Th17 and TIM3 + IFN-γ + Th1 cells ratios, increased the proportion of Th1 and Treg cells in the spleen; suppressed TIM1 and TIM3,but increased IL-33 expression in the nasal mucosa in OVA-induced AR mice. R848 suppresses IL-25, IL-33 released and TIM1, TIM3 expression, which may contribute to its anti-allergic effects.

Effects of 1,25-dihydroxyvitamin D3 in an ovalbumin-induced allergic rhinitis model.

IL-17-producing Th17 cells play an important role in allergic airway diseases, but their local expression and regulation in allergic rhinitis (AR) is not well understood. This study investigated the effects of 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3) on T-bet expression, Th1 cells, Th2 cells, Th17 cells and IL-33-positive epithelial cells in AR. C57BL/6 mice were intranasally sensitized and challenged with ovalbumin (OVA), and 1,25-(OH)2D3 was intraperitoneally injected into AR mice. Cytokine levels were measured with enzyme-linked immunosorbent assays, phenotypic analysis of Th1, Th2 and Th17 cells in the spleen was completed with flow cytometry, and the CD4+IL-17+ cells in the Nasopharynx-associated lymphoid tissue (NALT) and IL-33-positive cells in nasal mucosa was evaluated with immunofluorescence microscopy. AR mice shown significantly increased Th2 and Th17 cell ratio in spleen, IL-17 level in serum, IL-5 and IL-13 levels in NALF but a lower number of IL-33-positive epithelial cells and Th1 response (Th1 and Tbet+Th1 cell ratio in the spleen and serum IFN-γ level) than the control mice.1,25-(OH)2D3 treatment significantly decreased the number of sneezing, nasal rubbing, OVA-sIgE and IL-17 in serum, IL-5 and IL-13 levels in NALF, Th17 cell ratio in the spleen and the histological of nasal mucosal but increased the number of IL-33-positive epithelial cells in AR mice. However, 1,25-(OH)2D3 treatment did not significantly influence IFN-γ level in serum, and Th1, Tbet+Th1 and Th2 cell ratio in spleen. Thus, 1,25-(OH)2D3 may exert anti-allergic effects by suppressing Th17 responses and local production of IL-5 and IL-13 cytokines.