Cultured Human Airway Epithelial Cells (Calu-3): A Model of Human Respiratory Function, Structure, and Inflammatory Responses

This article reviews the application of the human airway Calu-3 cell line as a respiratory model for studying the effects of gas concentrations, exposure time, biophysical stress, and biological agents on human airway epithelial cells. Calu-3 cells are grown to confluence at an air-liquid interface on permeable supports. To model human respiratory conditions and treatment modalities, monolayers are placed in an environmental chamber, and exposed to specific levels of oxygen or other therapeutic modalities such as positive pressure and medications to assess the effect of interventions on inflammatory mediators, immunologic proteins, and antibacterial outcomes. Monolayer integrity and permeability and cell histology and viability also measure cellular response to therapeutic interventions. Calu-3 cells exposed to graded oxygen concentrations demonstrate cell dysfunction and inflammation in a dose-dependent manner. Modeling positive airway pressure reveals that pressure may exert a greater injurious effect and cytokine response than oxygen. In experiments with pharmacological agents, Lucinactant is protective of Calu-3 cells compared with Beractant and control, and perfluorocarbons also protect against hyperoxia-induced airway epithelial cell injury. The Calu-3 cell preparation is a sensitive and efficient preclinical model to study human respiratory processes and diseases related to oxygen- and ventilator-induced lung injury

Risk Factor Analysis for 30-Day Readmission Rates of Newly Tracheostomized Children

Objectives: Pediatric patients undergo tracheostomy for a variety of reasons; however, medical complexity is common among these patients. Although tracheostomy may help to facilitate discharge, these patients may be at increased risk for hospital readmission. The purpose of this study was to evaluate our institutional rate of 30-day readmission for patients discharged with new tracheostomies and to identify risk factors associated with readmission. Study Design: A retrospective cohort study was conducted for all pediatric patients ages 0-18 years with new tracheostomies at our institution over a 36-month period. Methods: A chart review was performed for all newly tracheostomizedchildren from 2013 to 2016. We investigated documented readmissions within 30 days of discharge, reasons for readmission, demographic variables including age and ethnicity, initial discharge disposition, co-morbidities, and socioeconomic status estimated by mean household income by parental zip code. Results: 45 patients were discharged during the study time period. A total of 13 (28.9%) required readmission within 30 days of discharge. Among these 13 patients, the majority (61.5%) were readmitted for lower airway concerns, many (30.8%) were admitted for reasons unrelated to tracheostomy or respiratory concerns, and only one patient (7.7%) was readmitted for a reason related to tracheostomy itself (tracheostomalbreakdown). Age, ethnicity, discharge disposition, co-morbidities, and socioeconomic status were not associated with differences in readmission rates. Patients readmitted within 30 days had a higher number of admissions within the first year. Conclusion: Pediatric patients with new tracheostomies are at high risk for readmission after discharge from initial hospitalization. The readmissions are most likely secondary to underlying medical complexity rather than issues related specifically to the tracheostomy procedure.https://jdc.jefferson.edu/patientsafetyposters/1046/thumbnail.jp

大脳由来と小脳由来の初代培養アストロサイトは、アポトーシスに関連する細胞外ナトリウム感受性が異なる

Central pontine myelinolysis is one of the idiopathic or iatrogenic brain dysfunction, and the most common cause is excessively rapid correction of chronic hyponatraemia. While myelin disruption is the main pathology, as the diagnostic name indicates, a previous study has reported that astrocyte death precedes the destruction of the myelin sheath after the rapid correction of chronic low Na+ levels, and interestingly, certain brain regions (cerebral cortex, hippocampus, etc.) are specifically damaged but not cerebellum. Here, using primary astrocyte cultures derived from rat cerebral cortex and cerebellum, we examined how extracellular Na+ alterations affect astrocyte death and whether the response is different between the two populations of astrocytes. Twice the amount of extracellular [Na+] and voltage-gated Na+ channel opening induced substantial apoptosis in both populations of astrocytes, while, in contrast, one half [Na+] prevented apoptosis in cerebellar astrocytes, in which the Na+–Ca2+ exchanger, NCX2, was highly expressed but not in cerebral astrocytes. Strikingly, the rapid correction of chronic one half [Na+] exposure significantly increased apoptosis in cerebellar astrocytes but not in cerebral astrocytes. These results indicate that extracellular [Na+] affects astrocyte apoptosis, and the response to alterations in [Na+] is dependent on the brain region from which the astrocyte is derived.博士（医学）・乙第1346号・平成26年12月3日Copyright © 2014 John Wiley & Sons, Ltd

Pediatric polysomnography-flagging etiologies and impact on the clinical timeline

Background/objectiveThere is a paucity of literature regarding “flagging” abnormal sleep studies for expedited review. This single-center retrospective analysis (n = 266) of flagged polysomnography studies from 2019 to 2022 aimed to investigate flagging and its impact on the clinical timeline.MethodsTwo hundred sixty-six flagged polysomnography studies from 2019 to 2022 were retrospectively reviewed.ResultsFlagged study etiologies included repetitive brief oxygen desaturations (46.6%), sustained desaturations (32.3%), sustained hypercapnia (5.6%), or other concerning events (15.5%). The median time between a flagged study and scoring report finalization, medical intervention, and surgical intervention were 0 (2) days, 2 (3) days, 5 (11.25) days, and 44 (73) days, respectively. Patients with apnea–hypopnea index >30 had less time between a flagged study and surgical intervention (65.3 ± 96.7 days vs. 112 ± 119 days, p = 0.044).ConclusionAs anticipated, the time to surgical intervention was longer than to medical intervention. Patients with a higher disease severity experienced quicker scoring, report finalization, and surgical intervention