Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Biomedical E ngineer ing Preparation of ECM Scaffolds • Perfusion decellularization system was developed. • Needle delivery (A) of decellularization solution into muscle belly (B) • Solution perfused through muscle and out to waste (C) • Flow (ml/hr) controlled to four units with syringe pump (D) Biomedical E ngineer ing Decellularized Skeletal Muscle (DSM) Biomedical E ngineer ing Decellularized Skeletal Muscle (DSM) VML Injury and Repair Biomedical E ngineer ing • Hind limb of mature (3 month) Fisher 344 rats. • Tibialis anterior (TA) VML injury created using 8mm biopsy punch (depth = 3mm) • Three treatment groups 1. Unrepaired (VML) 2. DSM 3. DSM + minced muscle (MM) • Contralateral limb untreated to serve as a comparative control (normal) • N=8 / treatment group • 3 month recovery period Biomedical E ngineer ing Muscle Electophysiology • At 3 months post-op peak TA contractile force (N) was measured. • Foot was secured to 10N force force transducer. • Peroneal nerve was stimulated with needle electrodes at • 5V at 150Hz, • Pulse width of 0.1 ms • Pulse length 400 ms. • Average of 5 contractions, force normalized to animal weight. Muscle Electrophysiology Biomedical E ngineer ing • Average contractile force (% normal) VML: 62±16% DSM: 73±13% DSM+MM: 78±14% • Trend: increased contractile force with repair strategies • DSM + MM increased contractile force by 26% (compared to unrepaired) * p<0.05 students t-test Biomedical E ngineer ing TA Mass & Gross Anatomy • TAs were harvest, weighed, imaged and then flash frozen in liquid N2. • Treated and control muscles were all smaller than normal contralateral muscles. • Implant sites were generally visible. * • Muscle mass (% contralateral) was modestly increased following DSM+MM treatment * p<0.1 students t-test Biomedical E ngineer ing Histology • Muscle samples cryosectioned (8um). • Immunostained for the presence of collagen type I (red) and myosin heavy chain (green). • DSM and unrepaired defects were strongly immunoreactive to collagen type 1, suggesting connective tissue healing (scarring). • DSM + MM sample defect sites were less pronounced.