Efficiency of percutaneous transhepatic cholangioscopy in the treatment of biliary complications after liver transplantation.

BACKGROUND: Percutaneous transhepatic cholangioscopy (PTCS) has provided an alternative therapeutic option for handling refractory biliary complications in liver transplanted recipients. This study aimed to evaluate short-term PTCS efficiency in the management of biliary complications following liver transplantation. METHODS: Clinical data of 25 patients who received therapeutic PTCS due to biliary complications after liver transplantation were retrospectively analyzed. RESULTS: Therapeutic PTCS was successfully performed in 25 patients. Biliary complications were anastomotic strictures in seven cases, intrahepatic cholangiolithiasis in four cases, extra-and intrahepatic cholangiolithiasis in three cases, choledocholithiasis complicated with anastomotic strictures in four cases, intrahepatic cholangiolithiasis complicated with non-anastomotic strictures in one case, intrahepatic cholangiolithiasis complicated with anastomotic strictures in five cases, intrahepatic cholangiolithiasis complicated with anastomotic strictures and ischemic cholangitis in one case. The median time between liver transplantation and first PTCS was 24 months, and median times of PTCS was 2.6. Clinical manifestations were significantly improved in most patients after PTCS, and biliary complications were successfully managed through PTCS in 15 cases, which were partially effective in eight cases and ineffective in two cases. PTCS was more effective in tackling anastomotic strictures and cholangiolithiasis. CONCLUSION: PTCS was an effective therapeutic modality for treating refractory biliary complications following liver transplantation.

Transfection of the DAAO gene and subsequent induction of cytotoxic oxidative stress by D-alanine in 9L cells.

D-amino acid oxidase (DAAO) can catalyze the dehydrogenation of D-amino acids, such as D-alanine, to the corresponding amino acids and is then reoxidized by molecular oxygen to yield hydrogen peroxide, a reactive oxygen species, which reacts with DNA, lipids and protein, inducing cell death. This study investigated whether rat glioma 9L cells infected with the recombinant retrovirus containing the DAAO cDNA fragment can be induced in order to undergo cytotoxic oxidative stress by D-alanine. The recombinant retroviral vector, plzrus-DAAO-FLAG-GFP (pl-Dfg), was constructed and used to transfect packaged phoenix cells. The supernatant containing recombinant retroviral particles from the transfected phoenix cells was harvested and utilized to infect target 9L cells. The cytotoxic oxidative stress of infected 9L cells was induced by the DAAO substrate, D-alanine. The plasmid pl-Dfg was successfully constructed. The high titer retroviral supernatant was obtained from the transfected phoenix cells. Infected 9L cells were less viable after exposure to D-alanine compared to the control group. Anti-apoptotic proteins significantly inhibited cell death. The DAAO/D-alanine system has a potential utility for gene therapy and may be an effective strategy for the treatment of brain cancer and other malignant tumors.