ABSTRACT
<p><b>OBJECTIVE</b>To explore the optimal implantation strategy of tissue-engineered liver (TEL) constructed based on decellularized spleen matrix (DSM) in rats.</p><p><b>METHODS</b>DSM was prepared by freeze-thawing and perfusion with sodium dodecyl sulfate (SDS) of the spleen of healthy SD rats. Primary rat hepatocytes isolated using modified Seglen 2-step perfusion method were implanted into the DSM to construct the TEL. The advantages and disadvantages were evaluated of 4 transplant strategies of the TEL, namely ectopic vascular anastomosis, liver cross-section suture transplantation, intrahepatic insertion and mesenteric transplantation.</p><p><b>RESULTS</b>The planting rate of hepatocytes in the DSM was (74.5∓7.7)%. HE staining and scanning electron microscopy showed satisfactory cell status, and immunofluorescence staining confirmed the normal expression of ALB and G6Pc in the cells. For TEL implantation, ectopic vascular anastomosis was difficult and resulted in a mortality rate of 33.3% perioperatively and massive thrombus formation in the matrix within 6 h. Hepatic cross-section suture failed to rapidly establish sufficient blood supply, and no viable graft was observed 3 days after the operation. With intrahepatic insertion method, the hepatocytes in the DSM could survive as long as 14 days. Mesenteric transplantation resulted in a hepatocyte survival rate of (38.3+7.1)% at 14 days after implantation.</p><p><b>CONCLUSION</b>TEL constructed based on DSM can perform liver-specific functions with a good cytological bioactivity. Mesenteric transplantation of the TEL, which is simple, safe and effective, is currently the optimal transplantation strategy.</p>
ABSTRACT
<p><b>BACKGROUND</b>Magnetic anchored surgical instruments (MASI), relying on magnetic force, can break through the limitations of the single port approach in dexterity. Individual characteristic abdominal wall thickness (ICAWT) deeply influences magnetic force that determines the safety of MASI. The purpose of this study was to research the abdominal wall characteristics in MASI applied environment to find ICAWT, and then construct an artful method to predict ICAWT, resulting in better safety and feasibility for MASI.</p><p><b>METHODS</b>For MASI, ICAWT is referred to the thickness of thickest point in the applied environment. We determined ICAWT through finding the thickest point in computed tomography scans. We also investigated the traits of abdominal wall thickness to discover the factor that can be used to predict ICAWT.</p><p><b>RESULTS</b>Abdominal wall at C point in the middle third lumbar vertebra plane (L3) is the thickest during chosen points. Fat layer thickness plays a more important role in abdominal wall thickness than muscle layer thickness. "BMI-ICAWT" curve was obtained based on abdominal wall thickness of C point in L3 plane, and the expression was as follow: f(x) = P1 × x 2 + P2 × x + P3, where P1 = 0.03916 (0.01776, 0.06056), P2 = 1.098 (0.03197, 2.164), P3 = -18.52 (-31.64, -5.412), R-square: 0.99.</p><p><b>CONCLUSIONS</b>Abdominal wall thickness of C point at L3 could be regarded as ICAWT. BMI could be a reliable predictor of ICAWT. In the light of "BMI-ICAWT" curve, we may conveniently predict ICAWT by BMI, resulting a better safety and feasibility for MASI.</p>