Background Understanding the changes in emergency department (ED) visit patterns during the coronavirus disease 2019 (COVID-19) outbreak is important for effectively operating EDs during the pandemic. We aimed to analyze the changes in pediatric ED visits during the COVID-19 pandemic and examine the relationship between the number of ED visits and the stringency of government social distancing measures. Methods This multicenter retrospective study used data of pediatric (age < 18 years) ED visits in Seoul metropolitan area from June 1, 2018, to May 31, 2020. Patient demographics, ED results, and diagnoses were compared during the COVID-19 period and the previous year. To evaluate the effect of the stringency of social distancing measures on the number of ED visits, a Poisson regression model was developed with month, year, and the average monthly Government Response Stringency Index (GRSI) as fixed effects. Results In total, 190,732 patients were included. The number of pediatric ED visits during the COVID-19 period was 58.1% lower than in the previous year. There were disproportionate decreases in the numbers of ED visits for children in early childhood (66.5%), low-acuity children (55.2-63.8%), those who did not use an ambulance (59.0%), and those visiting the ED for noninjury complaints (64.9%). The proportion of admissions increased from 11.9% to 16.6%. For every 10-point increase in the GRSI, there was a 15.1% decrease in monthly ED visits. Conclusion A striking decrease in pediatric ED visits was observed during the COVID-19 outbreak, the scale which was associated with the stringency of government policies. Changes in the number and characteristics of children visiting the ED should be considered to facilitate the effective operation of EDs during the pandemic.

Schwann cells (SCs), which produce neurotropic factors and adhesive molecules, have been reported previously to contribute to structural support and guidance during axonal regeneration; therefore, they are potentially a crucial target in the restoration of injured nervous tissues. Autologous SC transplantation has been performed and has shown promising clinical results for treating nerve injuries and donor site morbidity, and insufficient production of the cells have been considered as a major issue. Here, we performed differentiation of tonsil-derived mesenchymal stem cells (T-MSCs) into SC-like cells (T-MSC-SCs), to evaluate T-MSC-SCs as an alternative to SCs. Using SC markers such as CAD19, GFAP, MBP, NGFR, S100B, and KROX20 during quantitative real-time PCR we detected the upregulation of NGFR, S100B, and KROX20 and the downregulation of CAD19 and MBP at the fully differentiated stage. Furthermore, we found myelination of axons when differentiated SCs were cocultured with mouse dorsal root ganglion neurons. The application of T-MSC-SCs to a mouse model of sciatic nerve injury produced marked improvements in gait and promoted regeneration of damaged nerves. Thus, the transplantation of human T-MSCs might be suitable for assisting in peripheral nerve regeneration.

Stem cells are regarded as an important source of cells which may be used to promote the regeneration of skeletal muscle (SKM) which has been damaged due to defects in the organization of muscle tissue caused by congenital diseases, trauma or tumor removal. In particular, mesenchymal stem cells (MSCs), which require less invasive harvesting techniques, represent a valuable source of cells for stem cell therapy. In the present study, we demonstrated that human tonsil-derived MSCs (T-MSCs) may differentiate into myogenic cells in vitro and that the transplantation of myoblasts and myocytes generated from human T-MSCs mediates the recovery of muscle function in vivo. In order to induce myogenic differentiation, the T-MSC-derived spheres were cultured in Dulbecco's modified Eagle's medium/nutrient mixture F-12 (DMEM/F-12) supplemented with 1 ng/ml transforming growth factor-β, non-essential amino acids and insulin-transferrin-selenium for 4 days followed by culture in myogenic induction medium [low-glucose DMEM containing 2% fetal bovine serum (FBS) and 10 ng/ml insulin-like growth factor 1 (IGF1)] for 14 days. The T-MSCs sequentially differentiated into myoblasts and skeletal myocytes, as evidenced by the increased expression of skeletal myogenesis-related markers [including α-actinin, troponin I type 1 (TNNI1) and myogenin] and the formation of myotubes in vitro. The in situ transplantation of T-MSCs into mice with a partial myectomy of the right gastrocnemius muscle enhanced muscle function, as demonstrated by gait assessment (footprint analysis), and restored the shape of SKM without forming teratomas. Thus, T-MSCs may differentiate into myogenic cells and effectively regenerate SKM following injury. These results demonstrate the therapeutic potential of T-MSCs to promote SKM regeneration following injury.

Implementation of the KTAS changed admission and disposition patterns and reduced the LOS and mortality in the ED.

Purpose Epinephrine is a key drug for treating anaphylaxis; however, its underuse is still a significant issue worldwide. The objective of this study was to compare epinephrine use between pediatric and adult patients who were treated with anaphylaxis in the emergency department (ED). Methods The data were retrieved from the National Sample Cohort of South Korea, which contains claim data from the National Health Insurance Service. We included patients who visited the ED with a discharge code of anaphylaxis between 2004 and 2013. We assessed prescription information of epinephrine, antihistamine and systemic steroid, previous medical history and discharge disposition from the ED. The study population was categorized based on age at the visit. Results A total of 175 pediatric and 1,605 adult patients with anaphylaxis were identified. Only 42 (24%) of the pediatric patients were treated with epinephrine, while 592 (36.9%) of the adult patients were treated with epinephrine ( P = 0.001). Furthermore, the pediatric patients were less likely to be treated with systemic steroid than the adult patients (6.9% vs. 12.3%, P = 0.047). The odds ratios for the administration of epinephrine relative to the baseline in the 19-65 age group were 0.34 (95% confidence interval [CI], 0.15–0.67), 0.56 (95% CI, 0.28–1.03) and 0.79 (95% CI, 0.45–1.33) in the < 7, 7–12 and 13–18 age groups, respectively. Conclusions The pediatric patients with anaphylaxis experienced a lower rate of epinephrine injection use than the adult patients and the injection use decreased as age decreased.