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Wu T.,French Institute of Health and Medical Research | Wu T.,University of Strasbourg | Wu T.,Kunming Medical University | Bour G.,Research Institute Against Digestive Cancer | And 27 more authors.
Human Gene Therapy Methods | Year: 2015

We evaluated the possibility of introducing a combination of six oncogenes into primary porcine hepatocytes (PPH) using a lentiviral vector (LV)-mediated gene transfer in order to develop a porcine hepatocellular carcinoma model based on autologous transplantation of ex vivo-transformed hepatocytes. The six oncogenes were introduced into three plasmids, hence enabling the production of LVs encoding a luciferase reporter gene and hTERT+p53DD, cyclinD1+CDK4R24C, and c-mycT58A+HRasG21V genes, respectively. In order to improve the protection of the laboratory personnel manipulating such LVs, we used a compact cell culture cassette (CliniCell® device) as a closed cell culture system. We demonstrated that the CliniCell device allows to produce LVs, through plasmid transfection of 293T cells, and, after transfer to a second cassette, to transduce PPH with a similar efficacy as conventional open cell culture systems such as flasks or Petri dishes. Additionally, it is possible to cryopreserve at -80°C the transduced cells, directly in the CliniCell device used for the transduction. In conclusion, the use of a closed culture system for the safe handling of oncogene-encoding LVs lays the foundation for the development of porcine tumor models based on the autologous transplantation of ex vivo-transformed primary cells. © Copyright 2015 Mary Ann Liebert, Inc. Source

Liu Y.-Y.,Research Institute Against Digestive Cancer | Liu Y.-Y.,Chang Gung University | Kong S.-H.,Institute of Image Guided Surgery | Kong S.-H.,Seoul National University | And 8 more authors.
Surgical Endoscopy and Other Interventional Techniques | Year: 2015

Background: Biliary injuries remain a major concern in laparoscopic cholecystectomy. New intraoperative guidance modalities, including near-infrared fluorescence cholangiography, are under evaluation. Initial results showed limitations in visualizing the biliary tree in specific clinical situations. The aim of this study was to examine the feasibility and potentiality of fluorescence cholecysto-cholangiography performed with a direct injection of indocyanine green (ICG) in the gallbladder and to compare it to systemic injection in such situations. Materials and methods: Seven pigs were included in this non-survival study. In two pigs, the gallbladder was punctured by a percutaneous needle, and 1 mL of ICG in different concentrations (0.001, 0.01, 0.1, and 1 mg/mL) was sequentially injected. Visibility and pattern of the fluorescent signal around Calot’s triangle were examined and compared with those of two control pigs receiving 2.5 mg of intravenous ICG, 30 min prior to the operation. Different scenarios of cholecystitis were modeled using an injection of a mixture of blood and agarose gel around Calot’s triangle area in the remaining three pigs, and the applicability of direct intragallbladder injection methods was evaluated. Results: The fluorescent signal was identified immediately after intragallbladder injection, and the cystic duct became visible by 0.1 and 1 mg/mL of ICG. The whole cystic duct and the infundibulum of the gallbladder were clearly enhanced by intragallbladder ICG injection, but not by systemic injection. In the cholecystitis models, the cystic duct could be identified only after partial dissection, and fluorescence visualization of the gallbladder infundibulum provided crucial information to find the correct starting point of dissection. Conclusions: Fluorescence cholecysto-cholangiography through direct intragallbladder ICG injection could rapidly provide an adequate visualization of gallbladder neck and cystic duct and might be a valid option to increase the safety of cholecystectomy in case of cholecystitis. © 2015 Springer Science+Business Media New York Source

Selka F.,Abou Bekr Belkaid University Tlemcen | Selka F.,Research Institute Against Digestive Cancer | Nicolau S.,Research Institute Against Digestive Cancer | Agnus V.,Research Institute Against Digestive Cancer | And 3 more authors.
Computerized Medical Imaging and Graphics | Year: 2015

In minimally invasive surgery, the tracking of deformable tissue is a critical component for image-guided applications. Deformation of the tissue can be recovered by tracking features using tissue surface information (texture, color,...). Recent work in this field has shown success in acquiring tissue motion. However, the performance evaluation of detection and tracking algorithms on such images are still difficult and are not standardized. This is mainly due to the lack of ground truth data on real data. Moreover, in order to avoid supplementary techniques to remove outliers, no quantitative work has been undertaken to evaluate the benefit of a pre-process based on image filtering, which can improve feature tracking robustness. In this paper, we propose a methodology to validate detection and feature tracking algorithms, using a trick based on forward-backward tracking that provides an artificial ground truth data. We describe a clear and complete methodology to evaluate and compare different detection and tracking algorithms. In addition, we extend our framework to propose a strategy to identify the best combinations from a set of detector, tracker and pre-process algorithms, according to the live intra-operative data. Experimental results have been performed on in vivo datasets and show that pre-process can have a strong influence on tracking performance and that our strategy to find the best combinations is relevant for a reasonable computation cost. © 2014 Elsevier Ltd. Source

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