Paracrine Effects of Adipose-Derived Stem Cells on Keratinocytes and Dermal Fibroblasts

BACKGROUND: Adipose-derived stem cells (ASCs) are mesenchymal stem cells that have recently been applied to tissue repair and regeneration. Keratinocytes and dermal fibroblasts play key roles in cutaneous wound healing. OBJECTIVE: We investigated the paracrine effects of ASCs on HaCaT cells (i.e., immortalized human keratinocytes) and human dermal fibroblasts to explore the mechanism of the effects of ASCs on cutaneous wound healing. METHODS: HaCaT cells and primary cultured human dermal fibroblasts were treated with 50% conditioned medium of ASCs (ASC-CM). Viability, in vitro wound healing, and fibroblast-populated collagen lattice contraction assays were conducted, and reverse transcription-polymerase chain reaction (RT-PCR) for the type I procollagen alpha1 chain gene was performed. RESULTS: The proliferation of HaCaT cells and fibroblasts was increased by ASC-CM in the viability assay. ASC-CM promoted in vitro wound healing of HaCaT cells and increased the contraction of the fibroblast-populated collagen lattice. RT-PCR showed that the transcription of the type I procollagen alpha1 chain gene in fibroblasts was upregulated by ASC-CM. CONCLUSION: The stimulatory effect of ASC on cutaneous wound healing may be partially mediated by paracrine effects of ASCs on other skin cells. Application of ASCs or ASC-derived molecules could be an innovative therapeutic approach in the treatment of chronic wounds and other conditions.

Unanticipated Post-anesthesia Admission to the Pediatric Intensive Care Unit / 대한마취과학회지

BACKGROUND: Unanticipated admission to the pediatric intensive care unit (PICU) associated with anesthesia may serve as an outcome measure to evaluate the quality of anesthesia care and as education material for residency training. METHODS: We reviewed the unanticipated PICU admissions after anesthesia during 1 year period in order to analyze patient pattern, causes, and specific therapeutic interventions. We also determined whether there were any preventable anesthetic factors responsible for PICU admission. RESULTS: There were 640 admissions to PICU from operating theatres, with 8 unanticipated admissions. Age of the patients ranged from 4 months to 14 years. The unanticipated admissions were distributed to all of the surgical departments. Of 8 unanticipated admissions, only one was considered a preventable feature and had intensive care. CONCLUSIONS: The unanticipated admissions to PICU from the operation theatre were not associated with age or department of surgery. The majority of the causes of unanticipated admission were respiratory problems, which show that the pediatric anesthesiologists have to pay special attention to the respiratory system during anesthesia.