Bayesian modelling of time series data (BayModTS)-a FAIR workflow to process sparse and highly variable data.

MOTIVATION: Systems biology aims to better understand living systems through mathematical modelling of experimental and clinical data. A pervasive challenge in quantitative dynamical modelling is the integration of time series measurements, which often have high variability and low sampling resolution. Approaches are required to utilize such information while consistently handling uncertainties. RESULTS: We present BayModTS (Bayesian modelling of time series data), a new FAIR (findable, accessible, interoperable, and reusable) workflow for processing and analysing sparse and highly variable time series data. BayModTS consistently transfers uncertainties from data to model predictions, including process knowledge via parameterized models. Further, credible differences in the dynamics of different conditions can be identified by filtering noise. To demonstrate the power and versatility of BayModTS, we applied it to three hepatic datasets gathered from three different species and with different measurement techniques: (i) blood perfusion measurements by magnetic resonance imaging in rat livers after portal vein ligation, (ii) pharmacokinetic time series of different drugs in normal and steatotic mice, and (iii) CT-based volumetric assessment of human liver remnants after clinical liver resection. AVAILABILITY AND IMPLEMENTATION: The BayModTS codebase is available on GitHub at https://github.com/Systems-Theory-in-Systems-Biology/BayModTS. The repository contains a Python script for the executable BayModTS workflow and a widely applicable SBML (systems biology markup language) model for retarded transient functions. In addition, all examples from the paper are included in the repository. Data and code of the application examples are stored on DaRUS: https://doi.org/10.18419/darus-3876. The raw MRI ROI voxel data were uploaded to DaRUS: https://doi.org/10.18419/darus-3878. The steatosis metabolite data are published on FairdomHub: 10.15490/fairdomhub.1.study.1070.1.

Building up a model family for inflammations.

The paper presents an approach for overcoming modeling problems of typical life science applications with partly unknown mechanisms and lacking quantitative data: A model family of reaction-diffusion equations is built up on a mesoscopic scale and uses classes of feasible functions for reaction and taxis terms. The classes are found by translating biological knowledge into mathematical conditions and the analysis of the models further constrains the classes. Numerical simulations allow comparing single models out of the model family with available qualitative information on the solutions from observations. The method provides insight into a hierarchical order of the mechanisms. The method is applied to the clinics for liver inflammation such as metabolic dysfunction-associated steatohepatitis or viral hepatitis where reasons for the chronification of disease are still unclear and time- and space-dependent data is unavailable.

When is it safe for the liver donor to be discharged home and prevent unnecessary re-hospitalizations? - A systematic review of the literature and expert panel recommendations.

BACKGROUND: Few data are available on discharge criteria after living liver donation (LLD). OBJECTIVES: To identify the features for fit for discharge checklist after LLD to prevent unnecessary re-hospitalizations and to provide international expert recommendations. DATA SOURCES: Ovid MEDLINE, Embase, Scopus, Google Scholar, and Cochrane Central. METHODS: Systematic review following PRISMA guidelines and recommendations using the GRADE approach derived from an international expert panel. The critical outcomes included were complications rates and liver function (defined by elevated bilirubin and INR) (CRD42021260725). RESULTS: Total 57/1710 studies were included in qualitative analysis and 28/57 on the final analysis. No randomized controlled trials were identified. The complications rate was reported in 20/28 studies and ranged from 7.8% to 71.2%. Post hepatectomy liver function was reported in 13 studies. The Quality of Evidence (QoE) was Low and Very-Low for complications rate and liver function test, respectively. CONCLUSIONS: Monitoring and prevention of donor complications should be crucial in decision making of discharge. Pain and diet control, removal of all drains and catheters, deep venous thrombosis prophylaxis, and use routine imaging (CT scan or liver ultrasound) before discharge should be included as fit for discharge checklist (QoE; Low | GRADE of recommendation; Strong). Transient Impaired liver function (defined by elevated bilirubin and INR), a prognostic marker of outcome after liver resection, usually occurs after donor right hepatectomy and should be monitored. Improving trends for bilirubin and INR value should be observed by day 5 post hepatectomy and be included in the fit for discharge checklist. (QoE; Very-Low | GRADE; Strong).

Simultaneous right-sided nephrectomy with orthotopic liver and kidney transplantation-An alternative method for patients with autosomal dominant polycystic liver and kidney disease.

PURPOSE: In patients suffering from autosomal dominant polycystic liver and kidney disease (ADPLKD), combined organ transplantation often poses a technical challenge due to the large volume of both organs. To simplify the transplantation procedure by improving the exposure of anatomical structures, we introduce a novel surgical technique of orthotopic liver and kidney transplantation. METHODS: The modified simultaneous liver and kidney transplantation technique via a right-sided L-incision included three steps: (1) right-sided nephrectomy in the recipient followed by (2) orthotopic liver transplantation in cava replacement technique and (3) the orthotopic kidney transplantation with arterial reconstruction to the right common iliac artery. RESULTS: In total, seven patients with ADPLKD were transplanted by using the modified transplantation technique. The mean operation time was 342.43 min (±68.77). Postoperative patients were treated for 6.28 days (±2.50) in the intensive care unit and were discharged from the surgical ward approximately 28 days (±5.66) after the operation with normal graft function. Complications associated with the use of the modified technique, such as bleeding, anastomotic stenosis, biloma, or urinoma, did not occur. CONCLUSION: Modified simultaneous liver and kidney transplantation is a safe alternative for patients with ADPLKD. By combining right-sided nephrectomy and orthotopic graft transplantation, the approach optimizes the exposure of anatomical structures and simplifies the transplantation procedure. Additionally, the modified transplantation technique does not require a particular organ explantation procedure and can be applied for all liver and kidney grafts.

Tissue-based miRNA mapping in alcoholic liver cirrhosis: different profiles in cirrhosis with or without hepatocellular carcinoma.

Context: Alcoholic liver cirrhosis is a significant risk factor for the development of hepatocellular carcinoma (HCC). The importance of tumour-associated cirrhosis in the development or progression of HCC is not understood. MiRNAs are important regulators for HCC development, but their role in HCC due to alcoholic liver cirrhosis is unclear.Objective: The aim of this study is the detection of miRNA expression in alcoholic liver cirrhosis, tumour-associated cirrhosis, and HCC.Materials and methods: We analysed the differences in the miRNA profiles of HCC, tumour-associated cirrhosis, and cirrhosis without HCC samples from 30 patients who underwent liver transplantation because of alcoholic liver disease.Results: Microarray analyses revealed 40 significantly differentially expressed miRNAs between HCC tissue and tumour-associated cirrhosis tissue. Furthermore, the microarray analysis discovered 56 differentially expressed miRNAs in tumour-associated cirrhosis and cirrhosis without HCC.Discussion: The differences of miRNA profile in alcoholic liver cirrhosis with and without HCC could improve understanding of HCC development, as well as lead to a new diagnostic tool in HCC screening.Conclusion: We were able to show for the first time, the differences of miRNA profile as promising biomarker in HCC, tumour-associated cirrhosis, and cirrhosis without HCC in context of alcoholic liver disease.

Milan criteria in the MELD era-is it justifiable to extend the limits for orthotopic liver transplantation?

BACKGROUND: The Milan criteria (MC) are widely used for the indication of liver transplantation (LTx) in hepatocellular carcinoma (HCC). Good long-term results have also been reported following LTx for patients exceeding the MC. In this article, we compare the overall and recurrence-free survival of our patients fulfilling and exceeding the MC according to the post-transplant histopathological results. PATIENTS AND METHODS: Data from 120 patients with HCC (22 females and 98 males) were analyzed. The median patient age was 61 years (Q1, Q3 54.7, 65.4), and the median MELD score was 11 (Q1, Q3 8, 15). The median follow-up period was 53 months (Q1, Q3 16.6, 78). Patients were categorized into established criteria (MC, up-to-seven (UTS), Asan criteria, AFP score), and the outcome of the individual groups was compared. RESULTS: Seventy-four of 120 patients fulfilled the MC, 86 patients met the UTS criteria, 85 patients fulfilled the Asan criteria, and 79 patients had an AFP score less than or equal to 2. The 1- and 5-year survival rates of all patients were 76.7% and 55.6%, respectively. In total, 14.2% of all patients (5.4% of patients who met the MC, 7% of patients who met the UTS criteria, 5.9% of patients who met the Asan criteria, and 6.3% of patients who had an AFP score less than 2) experienced recurrence. CONCLUSIONS: The outcomes of the patients were comparable to those reported in the current literature. In our population, similar recurrence and survival rates of the patients were noted for patients fulfilling the UTS criteria irrespective of fulfilling or exceeding the MC. Consequently, we consider using UTS criteria as the extended criterion for LTx indication.

The Role of Autophagy for the Regeneration of the Aging Liver.

Age is one of the key risk factors to develop malignant diseases leading to a high incidence of hepatic tumors in the elderly population. The only curative treatment for hepatic tumors is surgical removal, which initiates liver regeneration. However, liver regeneration is impaired with aging, leading to an increased surgical risk for the elderly patient. Due to the increased risk, those patients are potentially excluded from curative surgery. Aging impairs autophagy via lipofuscin accumulation and inhibition of autophagosome formation. Autophagy is a recycling mechanism for eukaryotic cells to maintain homeostasis. Its principal function is to degrade endogenous bio-macromolecules for recycling cellular substances. A number of recent studies have shown that the reduced regenerative capacity of the aged remnant liver can be restored by promoting autophagy. Autophagy can be activated via multiple mTOR-dependent and mTOR-independent pathways. However, inducing autophagy through the mTOR-dependent pathway alone severely impairs liver regeneration. In contrast, recent observations suggest that inducing autophagy via mTOR-independent pathways might be promising in promoting liver regeneration. Conclusion: Activation of autophagy via an mTOR-independent autophagy inducer is a potential therapy for promoting liver regeneration, especially in the elderly patients at risk.

Mammalian MSC from selected species: Features and applications.

Mesenchymal stromal/stem cells (MSC) are promising candidates for cellular therapy of different diseases in humans and in animals. Following the guidelines of the International Society for Cell Therapy, human MSC may be identified by expression of a specific panel of cell surface markers (CD105+, CD73+, CD90+, CD34-, CD14-, or CD11b-, CD79- or CD19-, HLA-DR-). In addition, multiple differentiation potential into at least the osteogenic, adipogenic, and chondrogenic lineage is a main criterion for MSC definition. Human MSC and MSC of a variety of mammals isolated from different tissues meet these criteria. In addition to the abovementioned, they express many more cell surface markers. Yet, these are not uniquely expressed by MSC. The gross phenotypic appearance like marker expression and differentiation potential is similar albeit not identical for MSC from different tissues and species. Similarly, MSC may feature different biological characteristics depending on the tissue source and the isolation and culture procedures. Their versatile biological qualities comprising immunomodulatory, anti-inflammatory, and proregenerative capacities rely largely on the migratory and secretory capabilities of MSC. They are attracted to sites of tissue lesion and secrete factors to promote self-repair of the injured tissue. This is a big perspective for clinical MSC applications in both veterinary and human medicine. Phase I/II clinical trials have been initiated to assess safety and feasibility of MSC therapies in acute and chronic disease settings. Yet, since the mode of MSC action in a specific disease environment is still unknown at large, it is mandatory to unravel the response of MSC from a given source onto a specific disease environment in suitable animal models prior to clinical applications. © 2017 International Society for Advancement of Cytometry.

Attenuation of Postoperative Acute Liver Failure by Mesenchymal Stem Cell Treatment Due to Metabolic Implications.

OBJECTIVE: To prevent posthepatectomy acute liver failure after extended resection by treatment with mesenchymal stem cells (MSCs). BACKGROUND: Liver tumors often require extended liver resection, overburdening metabolic and regenerative capacities of the remnant organ. Resulting dysfunction and failure may be improved by the proregenerative characteristics of MSCs. METHODS: Extended liver resection was performed in (DPPIV)-deficient F344-Fischer rats. Wild-type animals served as donors of peritoneal adipose-derived MSCs. These were predifferentiated in vitro into hepatocytic cells and delivered to the liver by splenic application. Liver-related blood parameters (international normalized ratio, bilirubin, aspartate aminotransferase, alanine aminotransferase) and liver histology (hematoxylin-eosin, Sudan III) were determined to monitor liver function. Metabolic changes were assessed by metabolomic analyses in the remnant liver and the serum. Liver damage and regeneration were quantified by determination of the apoptotic and proliferation rates. RESULTS: MSCs supported survival after partial hepatectomy. They decreased liver-related blood parameters indicative for the improvement of liver function. The extensive lipid accumulation in hepatocytes illustrating the metabolic overload after resection was attenuated. Treatment with MSCs normalized imbalance of amino acids, acylcarnitines, sphingolipids, and glycerophospholipids in the liver and blood. Furthermore, MSCs decreased the apoptotic rate and increased the proliferation rate. The experimental time period (48 hours) was too short to allow for integration of MSCs into the host liver. Thus, the mode of action was probably indirect. CONCLUSIONS: MSCs ameliorated hepatic dysfunction and improved liver regeneration after extended resection by paracrine mechanisms. They may represent a new therapeutic option to treat posthepatectomy acute liver failure.

Diagnosis of HCC for patients with cirrhosis using miRNA profiles of the tumor-surrounding tissue - A statistical model based on stepwise penalized logistic regression.

The presence of hepatocellular carcinoma (HCC) is a significant complication of cirrhosis because it changes the prognosis and the treatment of the patients. By now, contrast-enhanced CT and MR scans are the most reliable tools for the diagnosis of HCC; however, in some cases, a biopsy of the tumor is necessary for the final diagnosis. The aim of the study was to develop a diagnostic tool using the microRNA (miRNA) profiles of the tissue surrounding the HCC tumor combined with clinical parameters in statistical models. At a transplantation setting, 32 patients with HCC and cirrhosis (B) were compared to 22 patients suffering from cirrhosis only (A). The diagnosis and exclusion of HCC was confirmed following the histopathological examination of the explanted liver. The HCC patients were significantly older than the patients with cirrhosis only (B: 60.6 and A: 49.9, p<0.001) and showed higher levels of ALT (A: 0.76µkat/l, B: 1.02µkat/, p=0.006) and AFP (A: 5.8ng/ml, B: 70.3ng/ml, p<0.001), whereas the bilirubin levels were higher in the cirrhosis only group (p=0.002). Using age (cut-off 50.23years) and AFP (cut-off 4.2ng/ml) thresholds, the levels of expression of miR-1285-3p and miR-943 differentiated between the patients with HCC and cirrhosis from those with cirrhosis only with an accuracy of 96.3%. This is the first report about the use of stepwise penalized logistic regression and decision tree analyses of miRNA expressions in the tumor-surrounding tissue combined with clinical parameters for the diagnosis of HCC.

The value of hepatic resection in metastasic renal cancer in the Era of Tyrosinkinase Inhibitor Therapy.

BACKGROUND: The value of liver-directed therapy (LDT) in patients with metastasic renal cell carcinoma (MRCC) is still an active field of research, particularly in the era of tyrosinkinase inhibitor (TKI) therapy. METHODS: The records of 35 patients with MRCC undergoing LDT of metastasic liver lesions between 1992 and 2015 were retrospectively analyzed. Immediate postoperative TKI was given in a subgroup of patients after LDT for metastasic lesions. Uni- and multivariate models were applied to assess overall survival (OS), progression-free survival (PFS) and disease-free survival (DFS). RESULTS: Following primary tumor (renal cell cancer) resection and LDT, respectively, median OS was better for a total of 16 patients (41 %) receiving immediate postoperative TKI with 151 and 98 months, when compared to patients without TKI therapy with 61 (p = 0.003) and 40 months (p = 0.032). Immediate postoperative TKI was associated with better median PFS (47 months versus 19 months; p = 0.023), whereas in DFS only a trend was observed (51 months versus 19 months; p = 0.110). CONCLUSIONS: LDT should be considered as a suitable additive tool in the era of TKI therapy of MRCC to the liver. In this context, postoperative TKI therapy seems to be associated with better OS and PFS, but not DFS.

Identification of Pathways in Liver Repair Potentially Targeted by Secretory Proteins from Human Mesenchymal Stem Cells.

BACKGROUND: The beneficial impact of mesenchymal stem cells (MSC) on both acute and chronic liver diseases has been confirmed, although the molecular mechanisms behind it remain elusive. We aim to identify factors secreted by undifferentiated and hepatocytic differentiated MSC in vitro in order to delineate liver repair pathways potentially targeted by MSC. METHODS: Secreted factors were determined by protein arrays and related pathways identified by biomathematical analyses. RESULTS: MSC from adipose tissue and bone marrow expressed a similar pattern of surface markers. After hepatocytic differentiation, CD54 (intercellular adhesion molecule 1, ICAM-1) increased and CD166 (activated leukocyte cell adhesion molecule, ALCAM) decreased. MSC secreted different factors before and after differentiation. These comprised cytokines involved in innate immunity and growth factors regulating liver regeneration. Pathway analysis revealed cytokine-cytokine receptor interactions, chemokine signalling pathways, the complement and coagulation cascades as well as the Januskinase-signal transducers and activators of transcription (JAK-STAT) and nucleotide-binding oligomerization domain-like receptor (NOD-like receptor) signalling pathways as relevant networks. Relationships to transforming growth factor ß (TGF-ß) and hypoxia-inducible factor 1-α (HIF1-α) signalling seemed also relevant. CONCLUSION: MSC secreted proteins, which differed depending on cell source and degree of differentiation. The factors might address inflammatory and growth factor pathways as well as chemo-attraction and innate immunity. Since these are prone to dysregulation in most liver diseases, MSC release hepatotropic factors, potentially supporting liver regeneration.

Alternative treatment of symptomatic pancreatic fistula.

BACKGROUND: The management of symptomatic pancreatic fistula after pancreaticoduodenectomy is complex and associated with increased morbidity and mortality. We here report continuous irrigation and drainage of the pancreatic remnant to be a feasible and safe alternative to total pancreatectomy. MATERIALS AND METHODS: Between 2005 and 2011, patients were analyzed, in which pancreaticojejunal anastomosis was disconnected because of grade C fistula, and catheters for continuous irrigation and drainage were placed close to the pancreatic remnant. Clinical data were monitored and quality of life was evaluated. RESULTS: A total of 13 of 202 patients undergoing pancreaticoduodenectomy required reoperation due to symptomatic pancreatic fistula. Ninety-day mortality of these patients was 15.3%. Median length of stay on the intensive care unit and total length of stay was 18 d (range 3-45) and 46 d (range 33-96), respectively. Patients with early reoperation (<10 d) had significantly decreased length of stay on the intensive care unit and operation time (P < 0.05). Global health status after a median time of 22 mo (range 6-66) was nearly identical, when compared with that of a healthy control group. Mean follow-up was 44.4 mo (±27.2). Four patients (36.6 %) died during the follow-up period; two patients from tumor recurrence, one patient from pneumonia, and one patient for unknown reasons. CONCLUSIONS: Treatment of pancreatic fistula by continuous irrigation and drainage of the preserved pancreatic remnant is a simple and feasible alternative to total pancreatectomy. This technique maintains a sufficient endocrine function and is associated with low mortality and reasonable quality of life.

A fat option for the pig: hepatocytic differentiated mesenchymal stem cells for translational research.

STUDY BACKGROUND: Extended liver resection is the only curative treatment option of liver cancer. Yet, the residual liver may not accomplish the high metabolic and regenerative capacity needed, which frequently leads to acute liver failure. Because of their anti-inflammatory and -apoptotic as well as pro-proliferative features, mesenchymal stem cells differentiated into hepatocyte-like cells might provide functional and regenerative compensation. Clinical translation of basic research requires pre-clinical approval in large animals. Therefore, we characterized porcine mesenchymal stem cells (MSC) from adipose tissue and bone marrow and their hepatocyte differentiation potential for future assessment of functional liver support after surgical intervention in the pig model. METHODS: Mesenchymal surface antigens and multi-lineage differentiation potential of porcine MSC isolated by collagenase digestion either from bone marrow or adipose tissue (subcutaneous/visceral) were assessed by flow cytometry. Morphology and functional properties (urea-, glycogen synthesis and cytochrome P450 activity) were determined during culture under differentiation conditions and compared with primary porcine hepatocytes. RESULTS: MSC from porcine adipose tissue and from bone marrow express the typical mesenchymal markers CD44, CD29, CD90 and CD105 but not haematopoietic markers. MSC from both sources displayed differentiation into the osteogenic as well as adipogenic lineage. After hepatocyte differentiation, expression of CD105 decreased significantly and cells adopted the typical polygonal morphology of hepatocytes. Glycogen storage was comparable in adipose tissue- and bone marrow-derived cells. Urea synthesis was about 35% lower in visceral than in subcutaneous adipose tissue-derived MSC. Cytochrome P450 activity increased significantly during differentiation and was twice as high in hepatocyte-like cells generated from bone marrow as from adipose tissue. CONCLUSION: The hepatocyte differentiation of porcine adipose tissue-derived MSC was shown for the first time yielding hepatocyte-like cells with specific functions similar in bone marrow and subcutaneous adipose tissue-derived MSC. That makes them good pre-clinical candidates for supportive approaches after liver resection in the pig.

Long-term health-related quality of life of living kidney donors: a single-center experience.

PURPOSE: Over the last few years, the evaluation of the health-related quality of life (HRQoL) of living kidney donors (LKD) has become of particular interest. The present study sought to evaluate the physical and mental HRQoL after kidney removal. The clinical and paraclinical course of these patients was examined, and the impact of preoperative donor evaluation, donor nephrectomy, and surgical recovery was evaluated. These data were compared with reference data of the general population. METHODS: Between 1998 and 2010, 72 living kidney donations were performed at our institution. To assess the HRQoL, two questionnaires-the Short Form 36 (SF-36) and a special LKD questionnaire-were sent to all 72 living donors. The records of the follow-up examinations of all 72 donors were retrospectively analyzed in order to assess the clinical and paraclinical data after kidney donation. RESULTS: Out of 72 donors, 55 (76.4 %) responded to the questionnaires. There was no change in systolic and diastolic blood pressure during the 7-year follow-up (p > 0.05). Mild proteinuria (>150 mg/l) was observed in six cases. Kidney donors had a higher HRQoL compared to the general population with mean values of the physical and mental summation scale (PCS and MCS, respectively) being 51.3 (SD = 7.6) and 50.6 (SD = 8.1). Peri- or postoperative complications were associated with lower values for physical function and physical component summary (PCS) (p < 0.05). DISCUSSION: Living donor kidney transplantation appears to be safe for donors. The HRQoL is excellent. To ensure a positive outcome for donors, a good clinical evaluation of potential donors is essential.

Quantifying fat zonation in liver lobules: an integrated multiscale in silico model combining disturbed microperfusion and fat metabolism via a continuum biomechanical bi-scale, tri-phasic approach.

Metabolic zonation refers to the spatial separation of metabolic functions along the sinusoidal axes of the liver. This phenomenon forms the foundation for adjusting hepatic metabolism to physiological requirements in health and disease (e.g., metabolic dysfunction-associated steatotic liver disease/MASLD). Zonated metabolic functions are influenced by zonal morphological abnormalities in the liver, such as periportal fibrosis and pericentral steatosis. We aim to analyze the interplay between microperfusion, oxygen gradient, fat metabolism and resulting zonated fat accumulation in a liver lobule. Therefore we developed a continuum biomechanical, tri-phasic, bi-scale, and multicomponent in silico model, which allows to numerically simulate coupled perfusion-function-growth interactions two-dimensionally in liver lobules. The developed homogenized model has the following specifications: (i) thermodynamically consistent, (ii) tri-phase model (tissue, fat, blood), (iii) penta-substances (glycogen, glucose, lactate, FFA, and oxygen), and (iv) bi-scale approach (lobule, cell). Our presented in silico model accounts for the mutual coupling between spatial and time-dependent liver perfusion, metabolic pathways and fat accumulation. The model thus allows the prediction of fat development in the liver lobule, depending on perfusion, oxygen and plasma concentration of free fatty acids (FFA), oxidative processes, the synthesis and the secretion of triglycerides (TGs). The use of a bi-scale approach allows in addition to focus on scale bridging processes. Thus, we will investigate how changes at the cellular scale affect perfusion at the lobular scale and vice versa. This allows to predict the zonation of fat distribution (periportal or pericentral) depending on initial conditions, as well as external and internal boundary value conditions.

Approaching Thrombospondin-1 as a Potential Target for Mesenchymal Stromal Cells to Support Liver Regeneration after Partial Hepatectomy in Mouse and Humans.

Extended liver resection carries the risk of post-surgery liver failure involving thrombospondin-1-mediated aggravation of hepatic epithelial plasticity and function. Mesenchymal stromal cells (MSCs), by interfering with thrombospondin-1 (THBS1), counteract hepatic dysfunction, though the mechanisms involved remain unknown. Herein, two-thirds partial hepatectomy in mice increased hepatic THBS1, downstream transforming growth factor-ß3, and perturbation of liver tissue homeostasis. All these events were ameliorated by hepatic transfusion of human bone marrow-derived MSCs. Treatment attenuated platelet and macrophage recruitment to the liver, both major sources of THBS1. By mitigating THBS1, MSCs muted surgery-induced tissue deterioration and dysfunction, and thus supported post-hepatectomy regeneration. After liver surgery, patients displayed increased tissue THBS1, which is associated with functional impairment and may indicate a higher risk of post-surgery complications. Since liver dysfunction involving THBS1 improves with MSC treatment in various animal models, it seems feasible to also modulate THBS1 in humans to impede post-surgery acute liver failure.

Portal venous contrast enhancement ratio of the adrenal glands and spleen as prognostic marker of mortality in patients with acute mesenteric ischemia.

PURPOSE: Contrast enhancement of the adrenal gland defined by computed tomography (CT) was previously analyzed as a prognostic factor for critically ill patients in various diseases. However, no study investigated this quantitative parameter in patients with acute mesenteric ischemia. Therefore, the aim of this study was to evaluate the prognostic value of the contrast enhancement of the adrenal glands in patients with clinically suspected AMI. METHODS: All patients with clinically suspected AMI were retrospectively assessed between 2016 and 2020. All patients underwent surgical exploration after CT imaging. Overall, 134 patients (52 female patients, 38.8%) with a mean age of 69.2 ± 12.4 years were included into the present analysis. For all patients, the preoperative CT was used to calculate the contrast media enhancement of the adrenal glands and the spleen. RESULTS: A total of 27 patients (18.5%) died within the first 24 h and over the following 30-day 94 patients (68.6%) died. There were statistically significant differences regarding the mean values for adrenal-to-spleen ratio for 24-h mortality (p = 0.001) and 30-day mortality (p = 0.004), whereas the radiodensity of the inferior vena cava and the radiodensity of the spleen was statistically significant between survivors and non-survivors after 30 days (p = 0.037 and p = 0.028, respectively). In Cox regression analysis, mean adrenal radiodensity was associated with 24-h mortality (HR 1.09, 95% CI 1.02-1.16, p = 0.01) but not with 30-day mortality (HR 1.03, 95% CI 0.99-1.07, p = 0.13). CONCLUSION: The contrast media enhancement of the adrenal gland is associated with the 24-h and 30-day mortality in patients with AMI. However, the prognostic relevance for translation into clinical routine needs to be validated in other cohorts.

Cross-species variability in lobular geometry and cytochrome P450 hepatic zonation: insights into CYP1A2, CYP2D6, CYP2E1 and CYP3A4.

There is a lack of systematic research exploring cross-species variation in liver lobular geometry and zonation patterns of critical drug-metabolizing enzymes, a knowledge gap essential for translational studies. This study investigated the critical interplay between lobular geometry and key cytochrome P450 (CYP) zonation in four species: mouse, rat, pig, and human. We developed an automated pipeline based on whole slide images (WSI) of hematoxylin-eosin-stained liver sections and immunohistochemistry. This pipeline allows accurate quantification of both lobular geometry and zonation patterns of essential CYP proteins. Our analysis of CYP zonal expression shows that all CYP enzymes (besides CYP2D6 with panlobular expression) were observed in the pericentral region in all species, but with distinct differences. Comparison of normalized gradient intensity shows a high similarity between mice and humans, followed by rats. Specifically, CYP1A2 was expressed throughout the pericentral region in mice and humans, whereas it was restricted to a narrow pericentral rim in rats and showed a panlobular pattern in pigs. Similarly, CYP3A4 is present in the pericentral region, but its extent varies considerably in rats and appears panlobular in pigs. CYP2D6 zonal expression consistently shows a panlobular pattern in all species, although the intensity varies. CYP2E1 zonal expression covered the entire pericentral region with extension into the midzone in all four species, suggesting its potential for further cross-species analysis. Analysis of lobular geometry revealed an increase in lobular size with increasing species size, whereas lobular compactness was similar. Based on our results, zonated CYP expression in mice is most similar to humans. Therefore, mice appear to be the most appropriate species for drug metabolism studies unless larger species are required for other purposes, e.g., surgical reasons. CYP selection should be based on species, with CYP2E1 and CYP2D6 being the most preferable to compare four species. CYP1A2 could be considered as an additional CYP for rodent versus human comparisons, and CYP3A4 for mouse/human comparisons. In conclusion, our image analysis pipeline together with suggestions for species and CYP selection can serve to improve future cross-species and translational drug metabolism studies.

Critical Evaluation of Discarded Donor Livers in the Eurotransplant Region: Potential Implications for Machine Perfusion.

BACKGROUND There are still many offered donor livers that are declined during the allocation process. Machine perfusion offers the option to evaluate (especially marginal) donor organs and to better decide whether a graft has the potential of being transplanted or not. There is a lack of clear detailed data on why organs are declined and how many donor livers would have the potential of being evaluated in the machine. MATERIAL AND METHODS We retrospectively reviewed 1356 donor livers between 2016 and 2018, which were offered by Eurotransplant and were declined during the allocation process; 284 grafts were from donor after cardiac death (DCD) and 1072 donations were from after brain death (DBD). The analysis was performed independently and blinded by senior transplant surgeons. RESULTS There were 904 (66.6%) donor livers with potential to be evaluated as suitable grafts in machine perfusion, whereas 417 (30.8%) organs were definitely not-transplantable, mainly due to liver cirrhosis, (untreated) donor malignancy, cardiac diseases of the donor leading to a hepatic congestion, and/or systemic infections in the donor. Donors in blood group "AB" were disproportionally often rejected. Due to missing data, 35 (2.6%) organs could not be sufficiently evaluated. CONCLUSIONS Our data suggest that many declined donor livers have potential of being evaluated by machine perfusion. Comprehensive use of machine perfusion is necessary and useful to improve the current organ shortage.