Obstruction of right ventricle-pulmonary artery bioprosthetic valved conduits can result from valvular degeneration and calcification or neointimal peel formation. From 1968 through 1989, 38 patients underwent repair of congenital heart malformation with a porcine xenograft extracardiac valved conduits from right ventricle to pulmonary artery. Of 27 patients who survived after initial repair, 14 patients (8 males and 6 females) were reoperated for conduit obstructions. Ages of patients at the reoperation ranged 5 to 20yr (mean age 11.8±3.6yr) and the interval between initial repair and reoperation ranged 3 to 9yr (mean 6.6±1.7yr). The obstructed conduits were replaced with mechanical valved conduits (4 patients), nonvalved conduits (7 patients) or outflow patches (3 patients). In a half of patients, obstructions occured at multiple levels within the conduits. Obstructions mainly resulted from valvular degeneration, neointimal peel formation and anastomotic narrowings. There was no operative death but one late death due to the infective endocarditis. The systolic pressure ratio of right ventricle to left ventricle (or aorta) decreased from 0.81±0.13 preoperatively to 0.48±0.10 postoperatively. From our experience, it is recommended to use adequate sized bioprosthetic valued conduits for patients' body weight at the initial repair and replace obstructed conduits to the large sized nonvalved conduit at reoperation if possible.

Auto-transplantation of adipose tissue is commonly used for the treatment of tissue defects in plastic surgery. The survival of the transplanted adipose tissue is not always constant, and one of reasons is the accelerated apoptosis of the implanted preadipocytes. We have recently established highly homogeneous preadipocytes, named ccdPAs. The aim of the current study was to evaluate the regulation of the potency of platelet-rich plasma (PRP) on the apoptosis of ccdPAs in vitro. PRP stimulated the proliferation of the preadipocytes in a dose-dependent manner, and the stimulatory activity of 2% PRP was significantly higher than that of 2% FBS or 2% platelet-poor plasma (PPP). The presence of 2% PRP significantly inhibited serum starvation- or TNF-alpha/cycloheximide-induced apoptosis in comparison to 2% FBS or 2% PPP. DAPK1 and Bcl-2-interacting mediator of cell death (BIM) mRNAs were reduced in the preadipocytes cultured with 2% PRP in comparison to those cultured in 2% FBS. The gene expression levels were significantly higher in cells cultured without serum in comparison to cells cultured with 2% FBS, and the levels in the cells with 2% PRP were reduced to 5-10% of those in the cells without serum. These results indicated that ccdPAs exhibit anti-apoptotic activities, in addition to increased proliferation, when cultured in 2% PRP in comparison to the same concentration of FBS, and that this was accompanied with reduced levels of DAPK1 and BIM mRNA expression in in vitro culture. PRP may improve the outcome of transplantation of adipose tissue by enhancing the anti-apoptotic activities of the implanted preadipocytes.
Adipocytes/*cytology ; Adipose Tissue/cytology/metabolism ; Apoptosis/*physiology ; Apoptosis Regulatory Proteins/antagonists & inhibitors/metabolism ; Calcium-Calmodulin-Dependent Protein Kinases/antagonists & inhibitors/metabolism ; Cell Culture Techniques/*methods ; *Cell Differentiation ; Cell Proliferation ; Cells, Cultured ; Gene Expression Regulation ; Humans ; Membrane Proteins/antagonists & inhibitors/metabolism ; *Platelet-Rich Plasma/metabolism/physiology ; Proto-Oncogene Proteins/antagonists & inhibitors/metabolism ; Tissue Transplantation