Different nonhypothermic preservation modalities have shown beneficial effects in liver transplantation models. This study compares controlled oxygenated rewarming (COR) to normothermic machine ...perfusion (NMP) to resuscitate liver grafts following cold storage (CS). Porcine livers were preserved for 18 hours by CS. Before reperfusion, the grafts were put on a machine perfusion device (Liver Assist) for 3 hours and were randomly assigned to COR (n = 6) or NMP (n = 5) and compared to standard CS. COR was carried out with the new Custodiol‐N solution, slowly increasing temperature from 8 °C to 20 °C during the first 90 minutes. NMP was carried out with diluted autologous blood at 37 °C for 3 hours. In both cases, the perfusate was oxygenated to partial pressure of oxygen > 500 mm Hg. Then liver viability was tested for 180 minutes during in vitro isolated sanguineous reperfusion. Activity of the mitochondrial caspase 9 was lower after COR. Measurement of tissue adenosine triphosphate and total adenine nucleotides at the end of the reconditioning period showed better energetic recovery after COR. COR also resulted in significantly lower enzyme leakage and higher bile production (P < 0.05) during reperfusion. This first comparison of COR and NMP as end‐ischemic reconditioning modalities demonstrates superior results in terms of mitochondrial integrity resulting in better energetic recovery, less hepatocellular injury, and ultimately superior function in favor of COR. Liver Transplantation 22 1223–1230 2016 AASLD
Klatskin tumors have a bad prognosis despite aggressive therapy. The role and extent of lymph node dissection during surgery is a matter of discussion. This retrospective study analyzes our current ...experience of surgical treatments in the last decade.
A retrospective single-center analysis of patients (
= 317) who underwent surgical treatment for Klatskin tumors. Univariable and multivariable logistic regression and Cox proportional analysis were performed. The primary endpoint was to investigate the role of lymph node metastasis for patient survival after complete tumor resection. The secondary endpoint was the prediction of lymph node status and long-term survival from preoperatively available parameters.
In patients with negative resection margins, a negative lymph node status was the prognosis-determining factor with a 1-, 3-, and 5-year survival rate of 87.7%, 37%, and 26.4% compared with 69.5%, 13.9%, and 9.3% for lymph-node-positive patients, respectively. Multivariable logistic regression for complete resection and negative lymph node status demonstrated only Bismuth type 4 (
= 0.01) and tumor grading (
= 0.002) as independent predictors. In multivariate Cox regression analysis, independent predictors of survival after surgery were the preoperative bilirubin level (
= 0.03), intraoperative transfusion (
= 0.002), and tumor grading (G) (
= 0.001).
Lymph node dissection is of utmost importance for adequate staging in patients undergoing surgery for perihilar cholangiocarcinoma. In spite of extensive surgery, long-term survival is clearly associated with the aggressiveness of the disease.
Esophagectomy carries a high risk of morbidity and mortality compared to other major surgeries. With the aim of creating an easy-to-use clinical preoperative risk assessment tool and to validate ...previously described risk factors for major complications following surgery, esophagectomies at two tertiary medical centers were analyzed.
A total of 450 patients who underwent esophagectomy for esophageal carcinoma at the University Medical Centre, Hamburg, or at the Medical Center University Duisburg-Essen, Germany (January 2008 to January 2020) were retrospectively analyzed. Epidemiological and perioperative data were analyzed to identify the risk factors that impact major complication rates. The primary endpoint of this study was to determine the incidence of major complications.
The mean age of the patients was 63 years with a bimodal distribution. There was a male predominance across the cohort (81% vs. 19%, respectively). Alcohol abuse (
= 0.0341), chronic obstructive pulmonary disease (
= 0.0264), and cardiac comorbidity (
= 0.0367) were associated with a significantly higher risk of major complications in the multivariate analysis. Neoadjuvant chemotherapy significantly reduced the risk of major postoperative complications (
< 0.0001).
Various patient-related risk factors increased the rate of major complications following esophagectomy. Patient-tailored prehabilitation programs before esophagectomy that focus on minimizing these risk factors may lead to better surgical outcomes and should be analyzed in further studies.
Oxygen persufflation has shown experimentally to favorably influence hepatic energy dependent pathways and to improve survival after transplantation. The present trial evaluated oxygen persufflation ...as adjunct in clinical liver preservation. A total of
= 116 adult patients (age: 54 (23-68) years, M/F: 70/46), were enrolled in this prospective randomized study. Grafts were randomized to either oxygen persufflation for ≥2 h (O2) or mere cold storage (control). Only liver grafts from donors ≥55 years and/or marginal grafts after multiple rejections by other centers were included. Primary endpoint was peak-aspartate aminotransferase (AST) level until post-operative day 3. Standard parameters including graft- and patient survival were analyzed by uni- and multivariate analysis. Both study groups were comparable except for a longer ICU stay (4 versus 3 days) of the donors and a higher recipient age (57 versus 52 years) in the O2-group. Serum levels of TNF alpha were significantly reduced after oxygen persufflation (
< 0.05). Median peak-AST values did not differ between the groups (O2: 580 U/l, control: 699 U/l). Five year graft- and patient survival was similar. Subgroup analysis demonstrated a positive effect of oxygen persufflation concerning the development of early allograft dysfunction (EAD), in donors with a history of cardiopulmonary resuscitation and elevated ALT values, and concerning older or macrosteatotic livers. This study favors pre-implantation O2-persufflation in concrete subcategories of less than optimal liver grafts, for which oxygen persufflation can be considered a safe, cheap and easy applicable reconditioning method.
Background
Although infant organ donors remain a rare source of organs for transplantation, technical challenges have resulted in increased rates of complications and inferior graft function. The aim ...of the present study was to investigate the outcomes of kidneys procured from juvenile and infant donors.
Patients and Methods
We evaluated all kidney transplants from deceased donors < 16 years of age performed at our center between 01/2008 and 08/2019. We defined three groups based on quartiles of donor body weight: <13 kg (infant donors), 13‐40 kg (juvenile donors), and > 40 kg (standard criteria donors). Clinical characteristics and outcomes were compared between groups.
Results
Ninety‐two transplants were included in this study. Out of 92 recipients, there were 32 (34.8%) adult and 60 (65.2%) pediatric patients. All groups demonstrated excellent graft function and survival on both short and long‐term follow‐up. 1‐year, 3‐year, and 5‐year graft survival rates for the standard criteria donor group were 100%, 95.2%, and 88.4%, respectively, compared with 95.8% for infant and 95% for juvenile donors at all times (P = .79). eGFR at 5 years was 98.9 ± 5.5, 74.1 ± 6.2, and 81.6 ± 6.9 mL/min/1.73 m2 for infant, juvenile, and standard criteria donors, respectively (P < .01).
Conclusion
Infant donor allografts can be transplanted with excellent long‐term outcomes in both pediatric and adult recipients. Implanting them as single allografts onto pediatric candidates allows for the transplantation of two patients. As such, pediatric recipients should be prioritized for these donor organs.
Introduction The treatment of perihilar Cholangiocarcinoma (pCCA) poses specific challenges not only due to its high perioperative complication rates but also due its dismal long-term prognosis with ...only a few long-term survivors (LTS) among the patients. Therefore, in this analysis characteristics and predictors of LTS in pCCA patients are investigated. Material and methods In this single center analysis, patients undergoing curative-intent liver resection for pCCA between 2010 and 2022 were categorized into long-term and short-term survivors (STS) excluding perioperative mortality. Binary logistic regression was used to determine key differences between the groups and to develop a prognostic composite variable. This composite variable was subsequently tested in the whole cohort of surgically treated pCCA patients using Cox Regression analysis for cancer-specific survival (CSS). Results Within a cohort of 209 individuals, 27 patients were identified as LTS (median CSS = 125 months) and 55 patients as STS (median CSS = 16 months). Multivariable analysis identified preoperative portal vein infiltration (OR = 5.85, p = 0.018) and intraoperative packed red blood cell (PRBC) transfusions (OR = 10.29, p = 0.002) as key differences between the groups. A prognostic composite variable based on these two features was created and transferred into a Cox regression model of the whole cohort. Here, the composite variable (HR = 0.35, p<0.001), lymph node metastases (HR = 2.15, p = 0.001) and postoperative complications (HR = 3.06, p<0.001) were identified as independent predictors of CSS. Conclusion Long-term survival after surgery for pCCA is possible and is strongly negatively associated with preoperative portal vein infiltration and intraoperative PRBC transfusion. As these variables are part of preoperative staging or can be modulated by intraoperative technique, the proposed prognostic composite variable can easily be transferred into clinical management to predict the oncological outcome of patients undergoing surgery for pCCA.
Machine perfusion by controlled oxygenated rewarming (COR) is feasible and safe in clinical application and result in a promising outcome. This study utilizes next-generation sequencing (NGS) to ...investigate the transcriptome of human liver tissue undergoing COR before liver transplantation. Cold-stored livers were subjected to machine-assisted slow COR for ~120 min before transplantation. Biopsies were taken before (preCOR) and after COR (postCOR) and 1 h after reperfusion (postRep). The samples were sequenced, using RNA-seq to analyze differential transcriptional changes between the different stages and treatments of the grafts. Comparison of differential gene expression preCOR and postCOR demonstrated 10 upregulated genes. postRep 97 and 178 genes were upregulated and 7 and 13 downregulated compared to preCOR and postCOR, respectively. A shift of gene expressions by machine perfusion to the TGF-beta pathway was observed. The present study demonstrates distinct transcriptome profiles associated with machine perfusion by COR and transplantation of human livers. Such data provide a deeper understanding of the molecular mechanisms of machine perfusion technology in human liver transplantation.
BACKGROUND Germany has the highest rate of patients dying or becoming unfit for transplant while waitlisted within the Eurotransplant region. Therefore, the aim of the current study was to analyze ...mortality as well as risk factors for mortality of candidates listed for liver transplantation at our center. MATERIAL AND METHODS Between 01/2011 and 12/2013, 481 adult patients were listed for primary liver transplantation (LT) at a single German center. Clinical and laboratory parameters were prospectively collected and retrospectively analyzed by univariable and multivariable logistic regression and Cox proportional hazards. RESULTS The mean model for end-stage liver disease (MELD) score of all liver transplant waitlist registrants (52.4 years, 60.1% male) was 16.9 (±10.2) at time of listing, with 10% of the listed patients having a MELD score of >32. After waitlisting, 133 (27.7%) candidates died within the follow-up period. Three-month-survival after listing for transplantation was 89% for patients ultimately receiving LT vs. 71.2% that did not receive LT (p<0.001). Multivariable analysis identified clinical parameters such as ICU treatment, preceding abdominal surgery, variceal bleeding, and ascites, as well as hydropic decompensation, as independent risk factors for waitlist mortality. CONCLUSIONS Consideration of independent risk factors of mortality within the MELD-based allocation system potentially improves assessment of individual urgency and might improve utilization of available organs.
Abstract Aims/hypothesis Pathological cardiac hypertrophy is an early phenotype in both types 1 and 2 diabetes. The primary stimulus for hypertrophic growth in diabetes is yet unknown and may involve ...neurohumoral stimulation of Gq-coupled receptors as well as direct glucose-dependent mechanisms. To discriminate between these hypertrophic stimuli we analyzed hypertrophic signalling pathways in wildtype and Gα11 -knockout mice. Methods Experimental diabetes was induced in wildtype and knockout mice by intraperitoneal injection of streptozotocin. 8 weeks after induction of diabetes myocardial function and structure was assessed by echocardiography before sacrifice. To identify prohypertrophic signalling pathways expression and translocation of protein kinase C isoforms α, βII , δ, ε and ζ were analyzed by immunohistochemical staining and immunoblot analysis after tissue fractionation. Changes in calcineurin signalling were identified by immunoblot analysis and functional assays. Expression levels of transcription factors GATA4 and NF-κB were quantified by real-time RT-PCR. Results Diabetic wildtype mice developed myocardial hypertrophy with preserved cardiac function. Calcineurin signalling was not different between the two groups. However, diabetic wildtype mice showed increased protein levels of PKC-α and PKC-ζ, translocation of PKC-α, -δ and -ε to cellular membranes and higher levels of NF-κB expression. In contrast, diabetic Gα11 -knockout mice showed no altered phenotype and no changes in NF-κB or PKC expression, although translocation of PKC-ε occurred as in wildtypes. Conclusions Gα11 is essential for the development of cardiac hypertrophy in type 1-diabetes. Stimulation of hypertrophic signalling through PKC-α, PKC-δ, PKC-ζ, and NF-κB appears to be receptor-dependent, whereas PKC-ε is activated by hyperglycemia, independent of Gα11.
Diabetes mellitus counts as a major risk factor for developing atherosclerosis. The activation of protein kinase C (PKC) is commonly known to take a pivotal part in the pathogenesis of ...atherosclerosis, though the influence of specific PKC isozymes remains unclear. There is evidence from large clinical trials suggesting excessive neurohumoral stimulation, amongst other pathways leading to PKC activation, as a central mechanism in the pathogenesis of diabetic heart disease. The present study was therefore designed to determine the role of Gq-protein signalling via Gα11 in diabetes for the expression of PKC isozymes in the coronary vessels.
The role of Gα11 in diabetes was examined in knockout mice with global deletion of Gα11 compared to wildtype controls. An experimental type 1-diabetes was induced in both groups by injection of streptozotocin. Expression and localization of the PKC isozymes α, βII, δ, ε, and ζ was examined by quantitative immunohistochemistry.
8 weeks after induction of diabetes a diminished expression of PKC ε was observed in wildtype animals. This alteration was not seen in Gα11 knockout animals, however, these mice showed a diminished expression of PKCζ. Direct comparison of wildtype and knockout control animals revealed a diminished expression of PKC δ and ε in Gα11 knockout animals.
The present study shows that expression of the nPKCs δ and ε in coronary vessels is under control of the g-protein Gα11. The reduced expression of PKC ζ that we observed in coronary arteries from Gα11-knockout mice compared to wildtype controls upon induction of diabetes could reduce apoptosis and promote plaque stability. These findings suggest a mechanism that may in part underlie the therapeutic benefit of RAS inhibition on cardiovascular endpoints in diabetic patients.
PDF
