RESUMO
OBJECTIVES: Cell-based therapies have demonstrated variable degrees of success in the management of myocardial infarction and heart failure. By inducing a myocardial infarction in a rat model, the effects of secretome from human induced pluripotent stem cells (HiPSCs) and human mesenchymal stem cells (hMSCs) on cardiac function and remodeling were investigated. METHODS: HiPSCs and hMSCs were cultured and after 12 cycles, secretome was collected. The quantification of stem cell growth factors was measured using the ELISA test. Thirty female Lewis rats underwent surgical ligation of the left coronary artery. The rats were then randomized (n=10/group) to receive one of three treatments injected into the peri-infarct area; normal saline, HiPSC and hMSC. Left ventricular ejection fraction (LVEF), fractional shortening (FS), histology and serum proteomics were evaluated in a blinded fashion both pre-operatively and at 2, 4 and 6 weeks. RESULTS: ELISA studies revealed, Platelet-derived growth factor (PDGF) concentration of 3.35± 0.031 ng/ml (0.68± 0.027ng/ml) for MSC-CM group, 3.44± 0.042 ng/ml (0.78± 0.03 ng/ml) for the HiPSC-CM group, 3.2± 0.107 ng/ml (0.64±0.013 ng/ml) for the MSC-pre-group, 3.1± 0.075 ng/ml (0.71± 0.013 ng/ml) for the HiPSC-pre group and 3.3± 0.047 ng/ml (0.71± 0.014ng/ml) for the HiPSC-pre-r group at 60 min in comparison to at (0 min).Compared to non-treated (NT), HiPSC and hMSC, treated rats demonstrated significant improvement in LVEF and FS, and significant reduction in scar size (p<0.05) at 4 and 6 weeks. Proteomic analysis detected the presence of Vascular endothelial growth factor (VEGF) in the serum of rats receiving HiPSC, which was absent in the NT and hMSC groups. CONCLUSION: The current study demonstrated a significant improvement of cardiac function and remodeling in response to secretome from HiPSCs and hMSCs. These findings suggest that secretome from HiPSCs may have potential therapy for acute myocardial infarction (MI) without the need of stem cell harvesting and implantation.
RESUMO
BACKGROUND: Deficiencies in non-technical skills (NTS) have been increasingly implicated in avoidable operating theatre errors. Accordingly, this study sought to characterize the impact of surgeon and anaesthetist non-technical skills on time to crisis resolution in a simulated operating theatre. METHODS: Non-technical skills were assessed during 26 simulated crises (haemorrhage and airway emergency) performed by surgical teams. Teams consisted of surgeons, anaesthetists and nurses. Behaviour was assessed by four trained raters using the Non-Technical Skills for Surgeons (NOTSS) and Anaesthetists' Non-Technical Skills (ANTS) rating scales before and during the crisis phase of each scenario. The primary endpoint was time to crisis resolution; secondary endpoints included NTS scores before and during the crisis. A cross-classified linear mixed-effects model was used for the final analysis. RESULTS: Thirteen different surgical teams were assessed. Higher NTS ratings resulted in significantly faster crisis resolution. For anaesthetists, every 1-point increase in ANTS score was associated with a decrease of 53·50 (95 per cent c.i. 31·13 to 75·87) s in time to crisis resolution (P < 0·001). Similarly, for surgeons, every 1-point increase in NOTSS score was associated with a decrease of 64·81 (26·01 to 103·60) s in time to crisis resolution in the haemorrhage scenario (P = 0·001); however, this did not apply to the difficult airway scenario. Non-technical skills scores were lower during the crisis phase of the scenarios than those measured before the crisis for both surgeons and anaesthetists. CONCLUSION: A higher level of NTS of surgeons and anaesthetists led to quicker crisis resolution in a simulated operating theatre environment.