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Schuler MJ, Becker D, Mueller M, Bautista Borrego L, Mancina L, Huwyler F, Binz J, Hagedorn C, Schär B, Gygax E, Weisskopf M, Sousa Da Silva RX, Antunes Crisóstomo JM, Dutkowski P, Rudolf von Rohr P, Clavien PA, Tibbitt MW, Eshmuminov D, Hefti M. Observations and findings during the development of a subnormothermic/normothermic long-term ex vivo liver perfusion machine. Artif Organs 2023; 47:317-329. [PMID: 36106378 DOI: 10.1111/aor.14403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Revised: 08/24/2022] [Accepted: 08/26/2022] [Indexed: 02/03/2023]
Abstract
BACKGROUND Ex situliver machine perfusion at subnormothermic/normothermic temperature isincreasingly applied in the field of transplantation to store and evaluateorgans on the machine prior transplantation. Currently, various perfusionconcepts are in clinical and preclinical applications. Over the last 6 years ina multidisciplinary team, a novel blood based perfusion technology wasdeveloped to keep a liver alive and metabolically active outside of the bodyfor at least one week. METHODS Within thismanuscript, we present and compare three scenarios (Group 1, 2 and 3) we werefacing during our research and development (R&D) process, mainly linked tothe measurement of free hemoglobin and lactate in the blood based perfusate. Apartfrom their proven value in liver viability assessment (ex situ), these twoparameters are also helpful in R&D of a long-term liver perfusion machine and moreover supportive in the biomedical engineering process. RESULTS Group 1 ("good" liver on the perfusion machine) represents the best liver clearance capacity for lactate and free hemoglobin wehave observed. In contrast to Group 2 ("poor" liver on the perfusion machine), that has shown the worst clearance capacity for free hemoglobin. Astonishingly,also for Group 2, lactate is cleared till the first day of perfusion andafterwards, rising lactate values are detected due to the poor quality of theliver. These two perfusate parametersclearly highlight the impact of the organ quality/viability on the perfusion process. Whereas Group 3 is a perfusion utilizing a blood loop only (without a liver). CONCLUSION Knowing the feasible ranges (upper- and lower bound) and the courseover time of free hemoglobin and lactate is helpful to evaluate the quality ofthe organ perfusion itself and the maturity of the developed perfusion device. Freehemoglobin in the perfusate is linked to the rate of hemolysis that indicates how optimizing (gentle blood handling, minimizing hemolysis) the perfusion machine actually is. Generally, a reduced lactate clearancecapacity can be an indication for technical problems linked to the blood supplyof the liver and therefore helps to monitor the perfusion experiments.Moreover, the possibility is given to compare, evaluate and optimize developed liverperfusion systems based on the given ranges for these two parameters. Otherresearch groups can compare/quantify their perfusate (blood) parameters withthe ones in this manuscript. The presented data, findings and recommendations willfinally support other researchers in developing their own perfusion machine ormodifying commercially availableperfusion devices according to their needs.
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Affiliation(s)
- Martin J Schuler
- Wyss Zurich - ETH Zurich/University of Zurich, Zurich, Switzerland
| | - Dustin Becker
- Wyss Zurich - ETH Zurich/University of Zurich, Zurich, Switzerland
| | - Matteo Mueller
- Department of Surgery, Swiss Hepato-Pancreato-Biliary and Transplantation Center, University Hospital Zurich, Zurich, Switzerland
| | - Lucia Bautista Borrego
- Department of Surgery, Swiss Hepato-Pancreato-Biliary and Transplantation Center, University Hospital Zurich, Zurich, Switzerland
| | - Leandro Mancina
- Department of Surgery, Swiss Hepato-Pancreato-Biliary and Transplantation Center, University Hospital Zurich, Zurich, Switzerland
| | - Florian Huwyler
- Macromolecular Engineering Laboratory, Department of Mechanical and Process Engineering, ETH Zurich, Zurich, Switzerland
| | - Jonas Binz
- Wyss Zurich - ETH Zurich/University of Zurich, Zurich, Switzerland
| | - Catherine Hagedorn
- Department of Surgery, Swiss Hepato-Pancreato-Biliary and Transplantation Center, University Hospital Zurich, Zurich, Switzerland
| | - Beatrice Schär
- Entwicklung biomedizinische Anwendungen, Securecell AG, Urdorf, Switzerland
| | - Erich Gygax
- Forschung und Entwicklung, Fumedica AG, Muri, Switzerland
| | - Miriam Weisskopf
- Center of Surgical Research, University Hospital Zürich, University of Zürich, Zurich, Switzerland
| | - Richard Xavier Sousa Da Silva
- Department of Surgery, Swiss Hepato-Pancreato-Biliary and Transplantation Center, University Hospital Zurich, Zurich, Switzerland
| | | | - Philipp Dutkowski
- Department of Surgery, Swiss Hepato-Pancreato-Biliary and Transplantation Center, University Hospital Zurich, Zurich, Switzerland
| | - Philipp Rudolf von Rohr
- Transport Processes and Reactions Laboratory, Department of Mechanical and Process Engineering, ETH Zurich, Zurich, Switzerland
| | - Pierre-Alain Clavien
- Department of Surgery, Swiss Hepato-Pancreato-Biliary and Transplantation Center, University Hospital Zurich, Zurich, Switzerland
| | - Mark W Tibbitt
- Macromolecular Engineering Laboratory, Department of Mechanical and Process Engineering, ETH Zurich, Zurich, Switzerland
| | - Dilmurodjon Eshmuminov
- Department of Surgery, Swiss Hepato-Pancreato-Biliary and Transplantation Center, University Hospital Zurich, Zurich, Switzerland
| | - Max Hefti
- Wyss Zurich - ETH Zurich/University of Zurich, Zurich, Switzerland
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Porcine Isolated Liver Perfusion for the Study of Ischemia Reperfusion Injury: A Systematic Review. Transplantation 2019; 102:1039-1049. [PMID: 29509572 DOI: 10.1097/tp.0000000000002156] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND Understanding ischemia reperfusion injury (IRI) is essential to further improve outcomes after liver transplantation (LT). Porcine isolated liver perfusion (ILP) is increasingly used to reproduce LT-associated IRI in a strictly controlled environment. However, whether ILP is a reliable substitute of LT was never validated. METHODS We systematically reviewed the current experimental setups for ILP and parameters of interest reflecting IRI. RESULTS Isolated liver perfusion was never compared with transplantation in animals. Considerable variability exists between setups, and comparative data are unavailable. Experience so far suggests that centrifugal pump(s) with continuous flow are preferred to reduce the risk of embolism. Hepatic outflow can be established by cannulation of the inferior vena cava or freely drained in an open bath. Whole blood at approximately 38°C, hematocrit of 20% or greater, and the presence of leukocytes to trigger inflammation is considered the optimal perfusate. A number of parameters related to the 4 liver compartments (hepatocyte, cholangiocyte, endothelium, immune cells) are available; however, their significance and relation to clinical outcomes is not well described. CONCLUSIONS Porcine ILP provides a reproducible model to study early IRI events. As all models, it has its limitations. A standardization of the setup would allow comparison of data and progress in the field.
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Eshmuminov D, Leoni F, Schneider MA, Becker D, Muller X, Onder C, Hefti M, Schuler MJ, Dutkowski P, Graf R, Rudolf von Rohr P, Clavien PA, Bautista Borrego L. Perfusion settings and additives in liver normothermic machine perfusion with red blood cells as oxygen carrier. A systematic review of human and porcine perfusion protocols. Transpl Int 2018; 31:956-969. [PMID: 29928775 DOI: 10.1111/tri.13306] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 06/10/2018] [Accepted: 06/18/2018] [Indexed: 12/30/2022]
Abstract
Liver machine perfusion (MP) at normothermic temperature (NMP) is a promising way to preserve and evaluate extended criteria donor livers. Currently, no consensus exists in methodology and perfusion protocols. Here, the authors performed a systematic literature search to identify human and porcine studies reporting on liver NMP with red blood cells. A qualitative synthesis was performed concerning technical aspects of MP, fluid composition, gas supply, and liver positioning. Thirty-seven publications including 11 human and 26 porcine studies were considered for qualitative synthesis. Control mode, pressure, flow, perfusate additives, and targeted blood gas parameters varied across human as well as porcine studies. For future analyses, it is advisable to report flow adjusted to liver weight and exact pressure parameters including mean, systolic, and diastolic pressure. Parenteral nutrition and insulin addition was common. Parenteral nutrition included amino acids and/or glucose without lipids. Taurocholic acid derivatives were used as bile flow promoters. However, short-term human NMP without taurocholic acid derivatives seems to be possible. This finding is relevant due to the lack of clinical grade bile salts. Near physiological oxygen tension in the perfusate is doable by adjusting gas flows, while blood gas parameters regulation needs more detailed description.
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Affiliation(s)
- Dilmurodjon Eshmuminov
- Department of Surgery, Swiss HPB and Transplantation Center, University Hospital Zurich, Zurich, Switzerland
| | - Filippo Leoni
- Department of Surgery, Swiss HPB and Transplantation Center, University Hospital Zurich, Zurich, Switzerland
| | - Marcel André Schneider
- Department of Surgery, Swiss HPB and Transplantation Center, University Hospital Zurich, Zurich, Switzerland
| | - Dustin Becker
- Wyss Zurich - ETH Zurich/University of Zurich, Zurich, Switzerland
| | - Xavier Muller
- Department of Surgery, Swiss HPB and Transplantation Center, University Hospital Zurich, Zurich, Switzerland
| | - Christopher Onder
- Institute for Dynamic Systems and Control, ETH Zurich, Zurich, Switzerland
| | - Max Hefti
- Wyss Zurich - ETH Zurich/University of Zurich, Zurich, Switzerland
| | - Martin J Schuler
- Wyss Zurich - ETH Zurich/University of Zurich, Zurich, Switzerland
| | - Philipp Dutkowski
- Department of Surgery, Swiss HPB and Transplantation Center, University Hospital Zurich, Zurich, Switzerland
| | - Rolf Graf
- Department of Surgery, Swiss HPB and Transplantation Center, University Hospital Zurich, Zurich, Switzerland
| | | | - Pierre-Alain Clavien
- Department of Surgery, Swiss HPB and Transplantation Center, University Hospital Zurich, Zurich, Switzerland
| | - Lucia Bautista Borrego
- Department of Surgery, Swiss HPB and Transplantation Center, University Hospital Zurich, Zurich, Switzerland
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Zhao LY, Liu S, Chen ZG, Zou JZ, Wu F. Cavitation enhances coagulated size during pulsed high-intensity focussed ultrasound ablation in an isolated liver perfusion system. Int J Hyperthermia 2016; 33:343-353. [DOI: 10.1080/02656736.2016.1255918] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Affiliation(s)
- Lu-Yan Zhao
- State Key Laboratory of Ultrasound Engineering in Medicine, College of Biomedical Engineering, Chongqing Medical University, Chongqing, China
- Department of Gynecology and Obstetrics, Xi'dian Group Hospital, Shaanxi Xi’an, China
| | - Shan Liu
- State Key Laboratory of Ultrasound Engineering in Medicine, College of Biomedical Engineering, Chongqing Medical University, Chongqing, China
| | - Zong-Gui Chen
- State Key Laboratory of Ultrasound Engineering in Medicine, College of Biomedical Engineering, Chongqing Medical University, Chongqing, China
| | - Jian-Zhong Zou
- State Key Laboratory of Ultrasound Engineering in Medicine, College of Biomedical Engineering, Chongqing Medical University, Chongqing, China
| | - Feng Wu
- State Key Laboratory of Ultrasound Engineering in Medicine, College of Biomedical Engineering, Chongqing Medical University, Chongqing, China
- Nuffield Department of Surgical Sciences, University of Oxford, Oxford, UK
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Izamis ML, Efstathiades A, Keravnou C, Leen EL, Averkiou MA. Dynamic contrast-enhanced ultrasound of slaughterhouse porcine livers in machine perfusion. ULTRASOUND IN MEDICINE & BIOLOGY 2014; 40:2217-2230. [PMID: 25023101 DOI: 10.1016/j.ultrasmedbio.2014.03.031] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2013] [Revised: 03/28/2014] [Accepted: 03/31/2014] [Indexed: 06/03/2023]
Abstract
The aim of this study was to enable investigations into novel imaging and surgical techniques by developing a readily accessible, versatile liver machine perfusion system. Slaughterhouse pig livers were used, and dynamic contrast-enhanced ultrasound was introduced to optimize the procurement process and provide real-time perfusion monitoring. The system comprised a single pump, oxygenator, bubble trap and two flowmeters for pressure-controlled perfusion of the vessels using an off-the-shelf perfusate at room temperature. Successful livers exhibited homogeneous perfusion in both the portal vein and hepatic artery with dynamic contrast-enhanced ultrasound, which correlated with stable oxygen uptake, bile production and hepatic resistance and normal histology at the end of 3 h of perfusion. Dynamic contrast-enhanced ultrasound revealed perfusion abnormalities invisible to the naked eye, thereby providing context to the otherwise systemic biochemical/hemodynamic measurements and focal biopsy findings. The model developed here is a simple, cost-effective approach for stable ex vivo whole-organ machine perfusion.
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Affiliation(s)
- Maria-Louisa Izamis
- Department of Mechanical and Manufacturing Engineering, University of Cyprus, Nicosia, Cyprus
| | | | - Christina Keravnou
- Department of Mechanical and Manufacturing Engineering, University of Cyprus, Nicosia, Cyprus
| | - Edward L Leen
- Department of Medicine, Imperial College, London, United Kingdom
| | - Michalakis A Averkiou
- Department of Mechanical and Manufacturing Engineering, University of Cyprus, Nicosia, Cyprus.
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Cho YE, Moon PG, Baek MC. An integrated proteomic and transcriptomic approach to understanding azathioprine- induced hepatotoxicity in rat primary hepatocytes. Electrophoresis 2014; 35:911-22. [PMID: 24338571 DOI: 10.1002/elps.201300137] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Revised: 11/28/2013] [Accepted: 11/29/2013] [Indexed: 01/15/2023]
Abstract
Azathioprine, an immunosuppressant, has gained a prominent position in the clinic for prevention of graft rejection in organ transplants, as well as dermatological autoimmune diseases. However, according to a number of research reports, hepatotoxicity, as one of the side effects, is a major obstacle in azathioprine therapy. In this study, an integrated toxicoproteomic and toxicotranscriptomic analysis was performed using rat primary hepatocytes, in order to gain insight into the in-depth pathway map related to azathioprine-induced hepatotoxicity. For proteomic and transcriptomic analysis, rat primary hepatocytes were exposed to azathioprine at IC20 concentration for 24 h. In particular, 2D LC-MS/MS and informatics-assisted label-free strategy for proteomic analysis were applied in order to increase the number of identified proteins and to improve the confidence of the quantitation results. Among 119 differentially identified protein species, 69 were upregulated and 50 were downregulated in the azathioprine-treated group. At the mRNA level, results of transcriptomic analysis showed increased transcription of 340 genes and decreased transcription of 63 genes in the azathioprine-treated group. Based on the analysis of transcriptomic and proteomic results using the DAVID program, drug metabolism/oxidative stress enzymes, xenobiotic metabolism by cytochrome P450, fatty acid metabolism, primary bile acid biosynthesis, contraction, inflammation metabolism, and mitogen-activated protein kinase (MAPK) kinase (ERK/JNK/p38 kinase) pathways were affected in azathioprine-treated hepatotoxicity. The effects on genes and proteins related to several important pathways were confirmed by real-time PCR and immunoblot analysis, respectively. This study is the first to report on relevant pathways related to azathioprine-induced hepatotoxicity through performance of integrated transcriptomic and proteomic analyses.
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Affiliation(s)
- Young-Eun Cho
- Department of Molecular Medicine, Cell and Matrix Biology Research Institute, School of Medicine, Kyungpook National University, Daegu, Republic of Korea
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Fructose 1-6 Bisphosphate Versus University of Wisconsin Solution for Rat Liver Preservation: Does FBP Prevent Early Mitochondrial Injury? Transplant Proc 2011; 43:1468-73. [DOI: 10.1016/j.transproceed.2011.02.023] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2010] [Accepted: 02/07/2011] [Indexed: 11/21/2022]
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S-nitroso-N-acetylcysteine: a promising drug for early ischemia/reperfusion injury in rat liver. Transplant Proc 2011; 42:4491-5. [PMID: 21168722 DOI: 10.1016/j.transproceed.2010.09.152] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2010] [Revised: 09/11/2010] [Accepted: 09/28/2010] [Indexed: 11/24/2022]
Abstract
BACKGROUND/AIMS Ischemia-reperfusion (I/R) injury is among the major causes of poor graft function early after liver transplantation that adversely influences patient survival. A variety of mediators have been implicated in the pathogenesis of I/R vascular injury, including nitric oxide (NO). Because of the beneficial effects of NO during preconditioning and reperfusion, strategies to prevent or ameliorate I/R injury through the stimulation of hepatic NO production are an area of significant clinical interest. We evaluated the role of S-nitroso-N-acetylcysteine (SNAC) as an NO donor in the prevention of liver I/R injury in an animal model. METHODS Adult male Wistar rats were randomly assigned to 3 experimental groups containing 5 animals each: the University of Wisconsin (UW) solution group; SNAC solution group; and SNAC-containing UW solution (SNAC+UW) group. Aspartate aminotransferase (AST), alanine aminotransferase (ALT) and lactate dehydrogenase (LDH) were determined in samples of the cold storage solution at 2, 4, and 6 hours of preservation. After 6 hours of cold storage, We applied a 15-minute reperfusion period. Thereafter, the reperfusion was interrupted with blood samples obtained to measure AST, ALT, LDH, and thiobarbituric acid reactive substances (TBARS). Hepatic fragments were processed for histologic analysis, and to determine of TBARS, catalase, and glutathione levels. RESULTS During cold preservation, AST and LDH were significantly lower among the SNAC than the UW group or the SNAC+UW group (P = .004 and P = .03, respectively). ALT was comparable among the groups (P = .3). After reperfusion, serum levels of AST, ALT, and LDH, as well as of hepatic TBARS and catalase showed no differences among the groups. Glutathione concentration was lower in the SNAC and SNAC+UW group (P < .001) compared with the UW group. We did not observe histologic signs of preservation injury. CONCLUSION The SNAC solution showed a greater protective effect to preserve rat livers during cold storage, but it was comparable with UW.
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Gaffke G, Nagel S, Hegemann O, Speck U, Grosse-Siestrup C, Jungnickel K, Stroszczynski C. [Introduction of a MR-compatible system for extracorporal perfusion of vital organs for MR-guided procedures--first-experiences]. Z Med Phys 2009; 19:21-8. [PMID: 19459582 DOI: 10.1016/j.zemedi.2008.08.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE To represent a MRI-compatible perfusion-system for extracorporeal perfusion of vital organs which permits the realisation of realistic experiments in a MR scanner. MATERIAL AND METHODS We performed MR examinations of explanted porcine livers and MR-guided interventions in porcine livers. Explanted organs were hemo-perfused under physiological conditions during the experiments. MR-sequences for diagnostic and interventional examinations were used. RESULTS The evaluated system was MRI-compatible. The achieved image quality of the used sequences showed excellent anatomical resolution. Planned experiments can be carried out with relatively low expenditure. Diagnostic as well as interventional investigations can be carried out. The used organs showed a stable function within physiological parameters up to 4 hours. CONCLUSION It is possible to perform ex vivo experiments under in vivo conditions with this system. With the used MR-compatible system MR-guided experimental interventions and thermal ablations can be carried out in explanted organs under in vivo conditions.
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Affiliation(s)
- Gunnar Gaffke
- Universitätsklinikum Magdeburg, Klinik für Radiologie und Nuklearmedizin, Leipziger Strasse 44, 39120 Magdeburg, Germany.
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Pinto Kruel C, Scherer de Fraga R, Dal Molin S, Mota S, Gasperin G, Cerski C, de Oliveira J, Álvares-da-Silva M. Hepatic Reperfusion in Rats: A New Model With Portal Arterialization in Studying Early Ischemia-Reperfusion Injury. Transplant Proc 2007; 39:3015-8. [DOI: 10.1016/j.transproceed.2007.05.084] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2006] [Revised: 02/09/2007] [Accepted: 05/22/2007] [Indexed: 11/25/2022]
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Risse F, Boese JM, Hess T, Mory M, Schäfer M, Gebhard MM, Schad LR. [An experimental organ model for magnetic resonance imaging]. Z Med Phys 2007; 17:205-11. [PMID: 17879818 DOI: 10.1016/j.zemedi.2006.10.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The investigation of reperfusion of organs after an ischaemic phase is of great interest in transplantation medicine. This work presents an experimental organ model for the examination of isolated canine livers by means of magnetic resonance imaging in reperfusion experiments. The perfusion of the organs inside a perfusate container in the scanner's head coil was performed with approximately physiological conditions for 1.5 hours. The pumps for the perfusate circulation were installed outside the scanner's room, where oxygenation and heating of the perfusate was also performed. In the MR examinations, T1- and T2-weighted sequences could be used to display the morphology of the organs and the spatial perfusion distribution after administration of contrast media. The images revealed oedema development during reperfusion and an inhomogenous perfusion distribution. Thus, the model allows for the non-invasive investigation of morphology and perfusion distribution in isolated reperfused organs.
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Affiliation(s)
- Frank Risse
- Medizinische Physik in der Radiologie, Deutsches Krebsforschungszentrum, Heidelberg, Germany
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Thewes S, Reed HK, Grosse-Siestrup C, Groneberg DA, Meissler M, Schaller M, Hube B. Haemoperfused liver as an ex vivo model for organ invasion of Candida albicans. J Med Microbiol 2007; 56:266-270. [PMID: 17244811 DOI: 10.1099/jmm.0.46760-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
To study invasion of the human fungal pathogen Candida albicans, several infection models have been established. This study describes the successful establishment of an ex vivo haemoperfused liver as a model to study invasion of C. albicans. Perfused organs from pigs could be kept functional for up to 12 h. By comparing a non-invasive and invasive strain of C. albicans and by following a time course of invasion, it was shown that the invasion process in the perfused liver infection model is very similar to the in vivo situation after intraperitoneal infection of mice. The advantage of this set-up compared with other models of invasion is discussed.
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Affiliation(s)
- Sascha Thewes
- Robert Koch Institute, Nordufer 20, 13353 Berlin, Germany
| | - Hilde-Kristin Reed
- Department of Comparative Medicine and Experimental Animal Science, Charité School of Medicine, 13353 Berlin, Germany
| | - Christian Grosse-Siestrup
- Department of Comparative Medicine and Experimental Animal Science, Charité School of Medicine, 13353 Berlin, Germany
| | - David A Groneberg
- Department of Comparative Medicine and Experimental Animal Science, Charité School of Medicine, 13353 Berlin, Germany
| | - Michael Meissler
- Department of Comparative Medicine and Experimental Animal Science, Charité School of Medicine, 13353 Berlin, Germany
| | - Martin Schaller
- Institute of Dermatology, Eberhard Karls University, 72076 Tübingen, Germany
| | - Bernhard Hube
- Robert Koch Institute, Nordufer 20, 13353 Berlin, Germany
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Abstract
During the past decade, the clinical applications of laparoscopic surgery in urology have been growing steadily. The laparoscopic version of various procedures, such as nephrectomy, is becoming the standard of care. This has led to an increased need for laparoscopic training in urology and focused the attention on the various modalities for laparoscopic skill acquisition. The common training modalities for laparoscopy are box trainers, animal and cadaveric laparoscopy, and virtual reality simulators. Each modality carries its own benefits to the practicing surgeon. The box trainers are the first practiced and are basic training simulators. They were first designed to help with training in basic laparoscopic skills and to assist surgeons in getting acquainted with instruments. However, these simple boxes are being upgraded constantly by tissue- and organ-specific models, allowing the surgeon to train in a convenient and cost-effective environment. This article describes the ways to work with box trainers, from basic skills to advanced laparoscopic tasks, and discusses the contribution of these trainers to real surgery as well as their role in defining criterion levels of surgical performance.
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Affiliation(s)
- Ran Katz
- Department of Urology, Hadassah Medical Centre, PO Box 12000 Ein Kerem, Jerusalem 91120 Israel.
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