Biomimetic hepatic lobules from three-dimensional imprinted cell sheets

Liver-tissue engineering has proven valuable in treating liver diseases, but the construction of liver tissues with high fidelity remains challenging. Here, we present a novel three-dimensional (3D)-imprinted cell-sheet strategy for the synchronous construction of biomimetic hepatic microtissues with high accuracy in terms of cell type, density, and distribution. To achieve this, the specific composition of hepatic cells in a normal human liver was determined using a spatial proteogenomics dataset. The data and biomimetic hepatic micro-tissues with hexagonal hollow cross-sections indicate that cell information was successfully generated using a homemade 3D-imprinted device for layer-by-layer imprinting and assembling the hepatic cell sheets. By infiltrating vascular endothelial cells into the hollow section of the assembly, biomimetic hepatic microtissues with vascularized channels for nutrient diffusion and drug perfusion can be obtained. We demonstrate that the resultant vascularized biomimetic hepatic micro-tissues can not only be integrated into a microfluidic drug-screening liver-on-a-chip but also assembled into an enlarged physiological structure to promote liver regeneration. We believe that our 3D-imprinted cell sheets strategy will open new avenues for biomimetic microtissue construction.

[Analysis of the prognosis and survival of patients with acute-on-chronic liver failure]

Objective: To explore the influencing factors and the impact of artificial liver treatment on the prognosis and survival of patients with acute-on-chronic liver failure (ACLF). Methods: Clinical data from 201 cases with ACLF from January 2016 to December 2019 was retrospectively analyzed. The survival rate was calculated by the Kaplan-Meier method, the log-rank test of univariate analysis, and the multivariate analysis of the stepwise Cox regression forward method. Results: The median survival time of patients was 6 months, and the survival rates at 6, 9, and 12 months were 51.2%, 38.3%, and 29.9%, respectively. In univariate analysis, age, presence or absence of hypertension and upper gastrointestinal bleeding, treatment method, model for end-stage liver disease (MELD) score, and cholinesterase were associated with prognosis (P < 0.05). Multivariate regression analysis results showed that MELD score was the main factor affecting the 1-year prognosis of ACLF patients (P = 0.002). Artificial liver treatment was beneficial for the 1-year prognosis of ACLF patients aged < 50 years or with a MELD score of ≥20 (P < 0.05 ). The relative risk ratio (RR) of mortality was 2.55 times higher in patients with advanced age (≥50 years old) than that of younger patients (P < 0.001). Regression analysis was performed using age as a stratification factor, and upper gastrointestinal bleeding was related to the prognosis of younger patients, while choline esterase was related to the prognosis of advanced age. Regression analysis after stratified MELD score showed that age and hypertension were related to the prognosis of patients with MELD score < 20, and treatment method and age were related to the prognosis of patients with MELD score≥20. Conclusion: Artificial liver treatment is beneficial for the 1-year prognosis of ACLF patients. Age, MELD score, hypertension, and upper gastrointestinal bleeding are independent risk factors affecting the prognosis of ACLF patients.

Observation on the Effect of Sequentially Combined Multi-modal Artificial Liver Treatment on HBV-related Acute-on-chronic Liver Failure

OBJECTIVE

To observe the short-term effect of sequentially combined multimodal artificial liver treatment (SCMALT) on HBV-related acute-on-chronic liver failure (HBV-ACLF).

METHODS

HBV-ACLF patients 155 cases undergoing artificial liver treatment were analyzed, and they were sorted into the SCMALT group and the conventional-modal artificial liver treatment (CALT) group. The clinical data of all patients were recorded and the serum levels of interleukin-8 (IL-8), chemokine interferon-inducible protein-10 (IP-10), and interleukin-6 (IL-6) were detected. The changes in the 30-day survival rate, cytokine level, model for end-stage liver disease (MELD) score, and complications of artificial liver treatment were analyzed.

RESULTS

After being followed up for 30 days, 104 patients survived and 51 died. At the end of the whole-course treatment, the decreases in IL-6, IP-10, and IL-8 levels and MELD scores in the SCMALT group were greater than in the CALT group. Cox regression suggested WBC (OR=1.066 ， 95% CI 1.012-1.123 ， P=0.017), AT-III activity (OR=0.935 ， 95% CI 0.907-0.964 ， P=0.000) at baseline, artificial liver treatment mode (OR=0.362，95% CI 0.164-0.800，P=0.012), number of artificial liver treatments (OR=0.656 ， 95% CI 0.436-0.986 ， P=0.043), spontaneous peritonitis (OR=0.337，95% CI 0.165-0.689，P=0.003), and hepatic encephalopathy (OR=0.104, 95% CI 0.028-0.388 ， P=0.001) were independent influencing factors of 30-day survival rate. SCMALT can significantly prolong the survival period of the patient. No obvious difference was shown in the proportions of bleeding and circulation instability between the two groups (P>0.05).

CONCLUSION

Compared with the CALT, SCMALT can more effectively remove inflammatory mediators and reduce the MELD score in HBV-ACLF patients, which can obviously ameliorate the prognosis, with less effect on the platelet count.

[Focusing on timing selection and whole-course management of liver transplantation treatment for patients with acute-on-chronic liver failure]

Acute-on-chronic liver failure (ACLF) is a clinical syndrome of acute decompensation accompanied by organ failure that occurs on the basis of chronic liver disease and has a high short-term mortality rate. Currently, there are still differences in relation to the definition of ACLF; thus, baseline characteristics and dynamic changes are important bases for clinical decision-making in patients with liver transplantation and others. The basic strategies for treating ACLF currently include internal medicine treatment, artificial liver support systems, and liver transplantation. Multidisciplinary active collaborative management throughout the whole course is of great significance for further improving the survival rate in patients with ACLF.

Inventing Engineered Organoids for end-stage liver failure patients

End-stage liver disease (ESLD) is a term used clinically in reference to a group of liver diseases with liver transplantation as the choice of treatment. Due to the limitations of liver transplantation, alternative treatments are needed. The use of primary human hepatocytes represents a valid alternative treatment, but the limitations related to hepatocyte quality, viability, function, conservation, and storage need to be overcome. Transplanted hepatocytes have only been followed for 6–9 months. Therefore, long-term causes of failures are not yet established, including rejection, apoptosis, or other causes. Other alternative therapies to replace liver transplantation include plasmapheresis, hemodiafiltration, and artificial livers. Unfortunately, these methods are highly limited due to availability, high cost, anaphylaxis reaction, development-deposition of immune-complexes, and restricted functionality. Liver organoids, which utilize stem cells instead of ‘impractical’ adult hepatocytes, may be a solution for the development of a complex bioartificial liver. Recent studies have explored the benefits of differentiating mature hepatocytes from stem cells inside a bioreactor. When the use of human-induced Hepatocytes (hiHeps) was investigated in mouse and pig models of liver failure, liver failure markers were decreased, hepatocyte function indicated by albumin synthesis improved, and survival time increased. Bioartificial liver treatment may decrease the infiltration of inflammatory cells into liver tissue by down-regulating pro-inflammatory cytokines.

[Effect of artificial liver with double plasma molecular absorb system model on patients' platelets and corresponding treatment strategy]

OBJECTIVE

To compare the effects of artificial liver treatment with double plasma molecular adsorption system(DPMAS) mode and traditional plasma exchange (PE) mode on platelets in patients, and to evaluate the clinical efficacy of recombinent human thrombopoietin (rhTPO) in the treatment of thrombocytopenia.

METHODS

A total of fifteen patients undergoing artificial liver with DPMAS model admitted to the Fifth Affiliated Hospital of Guangzhou Medical University from January 2018 to November 2020 were selected and included in the DPMAS group, and another 15 patients receiving PE were selected and included in the PE group. The improvement of clinical symptoms, such as fatigue, jaundice, oliguria, edema, etc. before and after artificial liver treatment was compared between the two groups, and the trend of blood routine (especially platelet), coagulation function and other indexes before and after treatment were compared between the two groups. The use of rhTPO and the number of platelets were recorded during treatment.

RESULTS

The improvement rate of clinical symptoms in DPMAS group was 86.67%, which was higher than that in PE group, but the difference was not statistically significant (P>0.05). There was no statistical significance in the outcome of the two groups within 90 days (P>0.05). There was no significant difference in white blood cell (WBC) and hemoglobin (HB) between the two groups after treatment (P>0.05). However, the level of platelet(PLT) in DPMAS group was significantly lower than that before treatment (P < 0.05), and was significantly lower than that in PE group (P < 0.05). After treatment, the international normalized ratio (INR) level in PE group was significantly improved (P < 0.05), but there was no significant difference in the INR level in DPMAS group (P>0.05). The patients in the DPMAS group received an average of (8.2±3.1) doses of rhTPO and (1.5±0.3) IU of platelet transfusions during hospitalization. In DMPAS group, platelets increased significantly after infusion of terbium.

CONCLUSION

Compared with PE mode, the artificial liver with DPMAS mode can reduce platelet levels in patients, but the application of rhTPO can stimulate platelet regeneration and increase platelet levels in the patients, thereby reducing the risk of bleeding due to platelet hypoplasia.

Natural polyphenol-based nanoengineering of collagen-constructed hemoperfusion adsorbent for the excretion of heavy metals

Designing a hemoperfusion adsorbent for the excretion therapy of toxic heavy metals still remains a great challenge due to the biosafety risks of non-biological materials and the desired highly efficient removal capacity. Herein, inspired from the homeostasis mechanism of plants, natural polyphenols are integrated with collagen matrix to construct a polyphenol-functionalized collagen-based artificial liver (PAL) for heavy metals excretion and free radicals scavenging therapy. PAL presents high adsorption capacities for Cu²⁺, Pb²⁺, and UO₂²⁺ ions, up to 76.98 μmol g^-1, 106.70 μmol g^-1, and 252.48 μmol g^-1, respectively. Remarkably, PAL possesses a high binding affinity for UO₂²⁺, Pb²⁺, and Cu²⁺ ions even in the complex serum environment with the presence of biologically-relevant ions (e.g., Mg²⁺, Ca²⁺ ions). Low hemolysis ratio (1.77%), high cell viability (> 85%), high plasma recalcification time (17.4 min), and low protein adsorption (1.02 μmol g^-1) indicate outstanding biocompatibility of this material. This natural polyphenol/collagen-based fully bio-derived hemoperfusion adsorbent provides a novel and potentially applicable strategy for constructing a hemoperfusion adsorbent for heavy metal ions excretion therapy with efficiency and biosafety.

[Prevention and treatment of infection after artificial liver treatment]

Artificial liver support system is an important method of treating liver failure, but after artificial liver treatment, secondary infections are usually amalgamated. Additionally, infection is a risk factor that aggravates liver failure, leading to an increased mortality and poor prognosis. Therefore, how to prevent and treat occurrence of infection in patients with liver failure is a key factor to improve the efficacy of artificial liver treatment.

[Value of serum alpha-fetoprotein for the prognostic evaluation of hepatitis B virus-related acute-on-chronic liver failure treated with artificial liver]

Objective: To investigate the value of alpha-fetoprotein (AFP) level on survived hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) patients treated with artificial liver. Methods: Clinical indicators of HBV-ACLF patients who were previously treated with plasma exchange-based artificial liver at our department were retrospectively collected. The difference of serum AFP level between the survival and the death group was compared at 30, 90 and 180 days after artificial liver treatment. The ROC curves of the subjects were plotted, and the sensitivity and specificity of AFP for the survival prediction of the patients at 30, 90 and 180 days after artificial liver surgery were calculated. AFP was divided into a high AFP group and a low AFP group using median value. AFP and postoperative survival predictive value at 30, 90, and 180 days were analyzed. Results: A total of 93 cases were included in this study. The AFP of the survival group at 30, 90, and 180 days was (231.0 ± 286.2) ng / ml, (237.69 ± 297) ng / ml, (229.44 ± 286.46) ng/ml, and the death group was (76.4 ± 104.7) ng/ml, (103.13 ± 116.99) ng / ml, (136.34 ± 2.9.29) ng/ml, respectively. AFP of the death group was significantly lower than the corresponding survival group (P < 0.05). Receiver operating characteristic (ROC) curve analyses indicated that the area under the curve (AUC) and its 95% confidence interval at 30, 90, and 180 days after artificial liver surgery were 0.739 (0.611 ~ 0.867), 0.675 (0.550 ~ 0.80), 0.653 (0.524 ~ 0.781), respectively. The median serum AFP value was 110 ng/ml, and the survival analysis showed that the survival time of the high AFP group was significantly higher than the low AFP group at 30 d (P = 0.01), 90 d (P = 0.04) and 180 d (P = 0.03) after artificial liver surgery. Conclusion: Serum AFP can be used as a predictor of survival for HBV-ACLF patients after artificial liver therapy and its clinical value needs to be further verified by the larger sample size.

End-stage liver failure: filling the treatment gap at the intensive care unit

End-stage liver failure is a condition of collapsing liver function with mortality rates up to 80. Liver transplantation is the only lifesaving therapy. There is an unmet need for therapy to extend the waiting time for liver transplantation or regeneration of the native liver. Here we review the state-of-the-art of non-cell based and cell-based artificial liver support systems, cell transplantation and plasma exchange, with the first therapy relying on detoxification, while the others aim to correct also other failing liver functions and/or modulate the immune response. Meta-analyses on the effect of non-cell based systems show contradictory outcomes for different types of albumin purification devices. For bioartificial livers proof of concept has been shown in animals with liver failure. However, large clinical trials with two different systems did not show a survival benefit. Two clinical trials with plasma exchange and one with transplantation of mesenchymal stem cells showed positive outcomes on survival. Detoxification therapies lack adequacy for most patients. Correction of additional liver functions, and also modulation of the immune system hold promise for future therapy of liver failure.

Novel hybrid three-dimensional artificial liver using human induced pluripotent stem cells and a rat decellularized liver scaffold

Introduction

Liver transplantation is currently the only curative therapy for end-stage liver failure; however, establishment of alternative treatments is required owing to the serious donor organ shortage. Here, we propose a novel model of hybrid three-dimensional artificial livers using both human induced pluripotent stem cells (hiPSCs) and a rat decellularized liver serving as a scaffold.

Methods

Rat liver harvesting and decellularization were performed as reported in our previous studies. The decellularized liver scaffold was recellularized with hiPSC-derived hepatocyte-like cells (hiPSC-HLCs) through the biliary duct. The recellularized liver graft was continuously perfused with the culture medium using a pump at a flow rate of 0.5 mL/min in a standard CO₂ (5%) cell incubator at 37 °C.

Results

After 48 h of continuous perfusion culture, the hiPSC-HLCs of the recellularized liver distributed into the parenchymal space. Furthermore, the recellularized liver expressed the albumin (ALB) and CYP3A4 genes, and secreted human ALB into the culture medium.

Conclusion

Novel hybrid artificial livers using hiPSCs and rat decellularized liver scaffolds were successfully generated, which possessed human hepatic functions.

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Human iPSC-derived hepatocytes were engrafted in a rat decellularized liver scaffold.

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The recellularized liver expressed human liver-related markers ALB and CYP3A4.

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The recellularized liver scaffold secreted human albumin.

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This novel model shows potential for artificial whole liver transplantation.

[Guideline for diagnosis and treatment of liver failure]. Zhonghua Gan Zang Bing Za Zhi. 2019;27:18-26. [PMID: 30685919 DOI: 10.3760/cma.j.issn.1007-3418.2019.01.006]

Liver failure is a familiar clinical severe liver disease syndrome with a very high mortality rate. Over the years, scholars from around the world have been exploring the definition, etiology, classification, types, diagnosis and treatment, and prognostic judgment of liver failure. Reflecting changes, that have transpired in recent years at home and abroad relevant to clinical evidence, this guideline updates the information previously published by the Chinese Society of Infectious Diseases, Chinese Medical Association, Liver Failure and Artificial Liver Group, Severe Liver Diseases and Artificial Liver Group, Chinese Society of Hepatology, Guidelines for Diagnosis and Treatment of Liver Failure (2012 Edition).

Artificial liver support in pigs with acetaminophen-induced acute liver failure

AIM

To establish a reversible porcine model of acute liver failure (ALF) and treat it with an artificial liver system.

METHODS

Sixteen pigs weighing 30-35 kg were chosen and administered with acetaminophen (APAP) to induce ALF. ALF pigs were then randomly assigned to either an experimental group (n = 11), in which a treatment procedure was performed, or a control group (n = 5). Treatment was started 20 h after APAP administration and continued for 8 h. Clinical manifestations of all animals, including liver and kidney functions, serum biochemical parameters and survival times were analyzed.

RESULTS

Twenty hours after APAP administration, the levels of serum aspartate aminotransferase, total bilirubin, creatinine and ammonia were significantly increased, while albumin levels were decreased (P < 0.05). Prothrombin time was found to be extended with progression of ALF. After continuous treatment for 8 h (at 28 h), aspartate aminotransferase, total bilirubin, creatinine, and ammonia showed a decrease in comparison with the control group (P < 0.05). A cross-section of livers revealed signs of vacuolar degeneration, nuclear fragmentation and dissolution. Concerning survival, porcine models in the treatment group survived for longer times with artificial liver system treatment (P < 0.05).

CONCLUSION

This model is reproducible and allows for quantitative evaluation of new liver systems, such as a bioartificial liver. The artificial liver system (ZHJ-3) is safe and effective for the APAP-induced porcine ALF model.

Clinical translation of bioartificial liver support systems with human pluripotent stem cell-derived hepatic cells

There is currently a pressing need for alternative therapies to liver transplantation. The number of patients waiting for a liver transplant is substantially higher than the number of transplantable donor livers, resulting in a long waiting time and a high waiting list mortality. An extracorporeal liver support system is one possible approach to overcome this problem. However, the ideal cell source for developing bioartificial liver (BAL) support systems has yet to be determined. Recent advancements in stem cell technology allow researchers to generate highly functional hepatocyte-like cells from human pluripotent stem cells (hPSCs). In this mini-review, we summarize previous clinical trials with different BAL systems, and discuss advantages of and potential obstacles to utilizing hPSC-derived hepatic cells in clinical-scale BAL systems.

Combined use of non-biological artificial liver treatments for patients with acute liver failure complicated by multiple organ dysfunction syndrome

BACKGROUND

Acute liver failure (ALF) caused by viral and non-viral hepatitis is often accompanied with severe metabolic disorders, the accumulation of toxic substances and continuous release and accumulation of a large number of endogenous toxins and inflammatory mediators. The present study aimed to investigate the effects of various combined non-biological artificial liver treatments for patients with acute liver failure (ALF) complicated by multiple organ dysfunction syndrome (MODS).

METHODS

Thirty-one patients with mid- or late-stage liver failure complicated by MODS (score 4) were randomly divided into three treatment groups: plasmapheresis (PE) combined with hemoperfusion (HP) and continuous venovenous hemodiafiltration (CVVHDF), PE+CVVHDF, and HP+CVVHDF, respectively. Heart rate (HR) before and after treatment, mean arterial pressure (MAP), respiratory index (PaO2/FiO2), hepatic function, platelet count, and blood coagulation were determined.

RESULTS

Significant improvement was observed in HR, MAP, PaO2/FiO2, total bilirubin (TBIL) and alanine aminotransferase (ALT) levels after treatment (P<0.05). TBIL and ALT decreased more significantly after treatment in the PE+CVVHDF and PE+HP+CVVHDF groups (P<0.01). Prothrombin time (PT) and albumin were significantly improved only in the PE+CVVHDF and PE+HP+CVVHDF groups (P<0.05). TBIL decreased more significantly in the PE+HP+CVVHDF group than in the HP+CVVHDF and PE+CVVHDF groups (P<0.05). The survival rate of the patients was 58.1% (18/31), viral survival rate 36.4% (4/11), and non-viral survival rate 70% (14/20).

CONCLUSION

Liver function was relatively improved after treatment, but PE+HP+CVVHDF was more efficient for the removal of toxic metabolites, especially bilirubin. The survival rate was significantly higher in the patients with non-viral liver failure than in those with viral liver failure.

Comparative study of efficacy of different types of artificial liver treatments in management of hepatitis B-associated liver failure

AIM: To investigate the clinical efficacy of plasma exchange (PE), plasma bilirubin adsorption (PBA), and PE combined with PBA in the treatment of hepatitis B-associated liver failure.

METHODS: The clinical data for 150 patients with hepatitis B-associated liver failure were retrospectively analyzed. These patients were randomly divided into a PE group, a PBA group, and a PE + PBA group. The volume of plasma consumed once, the effective rate, liver function, alanine aminotransferase (ALT), total bilirubin (TBIL), albumin (ALB), prothrombin time (PT), prothrombin time activity (PTA), creatinine (Cr) and plasma ammonia were recorded both before and after treatment and compared among the three groups. The incidence of adverse reactions was also observed.

RESULTS: The total effective rate was higher in the combination group than in the PE group and PBA group (65.45% vs 62.5%, 59.58%), but the difference was not statistically significant (both P > 0.05). TBIL was significantly decreased 4 hours after treatment compared to pre-treatment values in the PE, PBA and combination groups (410.3 µmol/L ± 208.6 µmol/L vs 292.5 µmol/L ± 175.4 µmol/L, 432.7 µmol/L ± 242.5 µmol/L vs 298.8 µmol/L ± 201.7 µmol/L, 468.2 µmol/L ± 241.6 µmol/L vs 288.5 µmol/L ± 184.5 µmol/L, all P < 0.05), but the decline showed no significantly statistical difference among the three groups. After treatment, PT was significantly shortened and PTA was increased in the combination group and PE group (both P < 0.05), but the changes showed no significant difference between the two groups (both P > 0.05). In the PBA group, PT was increased and PTA was decreased after treatment, but the differences were not significant (P > 0.05). Blood ammonia and Cr were significantly decreased in the three groups of patients after treatment (all P < 0.05), although there was no significantly statistical difference among the three groups. No serious adverse reactions occurred. The volume of plasma consumed once was significantly less in the combination group than in the PE group (1107.1 mL ± 212.3 mL vs 2911.5 mL ± 352.3 mL, P < 0.05).

CONCLUSION: PE combined with PBA can effectively reduce the amount of plasma consumed and the incidence of adverse reactions, improve survival and therefore represent a safe and effective treatment for hepatitis B-associated liver failure.

Therapeutic effect of plasma exchange combined with bilirubin absorption for hyperbilirubinemia: An analysis of 42 cases

AIM: To analyze the therapeutic effect of plasma exchange (PE) combined with bilirubin absorption (BA) in the treatment of hyperbilirubinemia.

METHODS: Forty-two patients with hyperbilirubinemia (55 events altogether) treated by PE combined with BA, including 28 males and 14 females, were enrolled. Their mean age was 52.14 years ± 8.52 years.

RESULTS: The overall response rate was 95.24% for the combination treatment group and 76.66% for the normal treatment group. There was a significant difference in the overall response rate between the two groups (P < 0.05). Both groups had a significant improvement in liver function after treatment. The combination treatment was more effective in the improvement of TBil and alkaline phosphatase (ALP) levels (both P < 0.05).

CONCLUSION: PE combined with BA is safe and effective in the treatment of hyperbilirubinemia.

Combined therapy for acute hepatic failure

Acute hepatic failure (AHF) is a devastating clinical syndrome characterized by rapid impairment of liver functions and development of encephalopathy, multiple organ failure, and in most cases cerebral edema. AHF has a high mortality rate. Although advances in drug treatment, artificial liver and liver transplantation have significantly improved the prognosis of AHF, there is still a lack of effective treatment for AHF because of its complicated etiopathogenesis, rapid progression and less clinical knowledge about managing the disease. There is an urgent need to develop effective treatments for AHF. This article aims to review recent advances in the treatment of AHF.

Clinical effect of artificial liver combined with 131I therapy versus conventional medical treatment in patients with hyperthyroidism and severe liver injury: an analysis of 40 cases

AIM: To evaluate the clinical effect of artificial liver combined with ¹³¹I therapy versus conventional medical treatment in patients with hyperthyroidism and severe liver injury.

METHODS: The clinical data for 40 patients with hyperthyroidism and severe liver injury who were treated at our hospital over the past 6 years were retrospectively analyzed to compare the efficacy of artificial liver combined with ¹³¹I therapy versus conventional medical treatment.

RESULTS: Twenty-five patients underwent artificial liver treatment, and of them 20 had a response and 5 had disease progression. The response rate was 80%. Fifteen patients received conventional medical treatment, and of them 6 had a response and 59 had disease progression, with a response rate of only 40%. Artificial liver treatment significantly improved liver function and thyroid function, shortened PT time and increased the cure rate.

CONCLUSION: Artificial liver combined with ¹³¹I therapy can significantly improve prognosis and reduce mortality in patients with hyperthyroidism and severe liver injury.

Comparison between bioartificial and artificial liver for the treatment of acute liver failure in pigs

AIM: To characterize and evaluate the therapeutic efficacy of bioartificial liver (BAL) as compared to that of continuous hemodiafiltration (CHDF) with plasma exchange (PE), which is the current standard therapy for fulminant hepatic failure (FHF) in Japan.

METHODS: Pigs with hepatic devascularization were divided into three groups: (1) a non-treatment group (NT; n = 4); (2) a BAL treatment group (BAL; n = 4), (3) a PE + CHDF treatment group using 1.5 L of normal porcine plasma with CHDF (PE + CHDF, n = 4). Our BAL system consisted of a hollow fiber module with 0.2 μm pores and 1 x 10¹⁰ of microcarrier-attached hepatocytes inoculated into the extra-fiber space. Each treatment was initiated 4 h after hepatic devascularization.

RESULTS: The pigs in the BAL and the PE + CHDF groups survived longer than those in the NT group. The elimination capacity of blood ammonia by both BAL and PE + CHDF was significantly higher than that in NT. Aromatic amino acids (AAA) were selectively eliminated by BAL, whereas both AAA and branched chain amino acids, which are beneficial for life, were eliminated by PE + CHDF. Electrolytes maintenance and acid-base balance were better in the CPE + CHDF group than that in the BAL group.

CONCLUSION: Our results suggest that PE + CHDF eliminate all factors regardless of benefits, whereas BAL selectively metabolizes toxic factors such as AAA. However since PE + CHDF maintain electrolytes and acid-base balance, a combination therapy of BAL plus CPE + CHDF might be more effective for FHF.

Preoperative risk factor analysis in orthotopic liver transplant-ation with pretransplant artificial liver support therapy

AIM: To assess the value of pre-transplant artificial liver support in reducing the pre-operative risk factors relating to early mortality after orthotopic liver transplantation (OLT).

METHODS: Fifty adult patients with various stages and various etiologies undergoing OLT procedures were treated with molecular adsorbent recycling system (MARS) as preoperative liver support therapy. The study included two parts, the first one is to evaluate the medical effectiveness of single MARS treatment with some clinical and laboratory parameters, which were supposed to be the therapeutical pre-transplant risk factors, the second part is to study the patients undergoing OLT using the regression analysis on preoperative risk factors relating to early mortality (30 d) after OLT.

RESULTS: In the 50 patients, the statistically significant improvement in the biochemical parameters was observed (pre-treatment and post-treatment). Eight patients avoided the scheduled Ltx due to significant relief of clinical condition or recovery of failing liver function, 8 patients died, 34 patients were successfully bridged to Ltx, the immediate outcome of this 34 patients within 30d observation was: 28 kept alive and 6 patients died.

CONCLUSION: Pre-operative SOFA, level of creatinine, INR, TNF-α, IL-10 are the main preoperative risk factors that cause early death after operation, MARS treatment before transplantion can relieve these factors significantly.