Assessment of biological functions for C3A cells interacting with adverse environments of liver failure plasma.

BACKGROUND: For its better differentiated hepatocyte phenotype, C3A cell line has been utilized in bioartificial liver system. However, up to now, there are only a few of studies working at the metabolic alternations of C3A cells under the culture conditions with liver failure plasma, which mainly focus on carbohydrate metabolism, total protein synthesis and ureagenesis. In this study, we investigated the effects of acute liver failure plasma on the growth and biological functions of C3A cells, especially on CYP450 enzymes. METHODS: C3A cells were treated with fresh DMEM medium containing 10% FBS, fresh DMEM medium containing 10% normal plasma and acute liver failure plasma, respectively. After incubation, the C3A cells were assessed for cell viabilities, lactate dehydrogenase leakage, gene transcription, protein levels, albumin secretion, ammonia metabolism and CYP450 enzyme activities. RESULTS: Cell viabilities decreased 15%, and lactate dehydrogenase leakage had 1.3-fold elevation in acute liver failure plasma group. Gene transcription exhibited up-regulation, down-regulation or stability for different hepatic genes. In contrast, protein expression levels for several CYP450 enzymes kept constant, while the CYP450 enzyme activities decreased or remained stable. Albumin secretion reduced about 48%, and ammonia accumulation increased approximately 41%. CONCLUSIONS: C3A cells cultured with acute liver failure plasma showed mild inhibition of cell viabilities, reduction of albumin secretion, and increase of ammonia accumulation. Furthermore, CYP450 enzymes demonstrated various alterations on gene transcription, protein expression and enzyme activities.

Efficacy of various combined blood purification techniques for treating patients with non-viral acute liver failure.

We sought to study the clinical efficacy of various combined blood purification techniques in patients with non-viral acute liver failure complicated by multiple organ dysfunction syndrome (MODS). For this purpose, 19 patients diagnosed of mid- or late-stage liver failure with MODS score-4 were randomly divided into 3 treatment groups of PE+HP+CVVHDF, PE+CVVHDF, and HP+CVVHDF, respectively. Pre- and post-treatment heart rate (HR), mean arterial pressure (MAP), arterial blood gases (pH, PaO2, and PaCO2), hepatic function, platelet count, and blood coagulation were determined. The data show significant improvement in HR, MAP, PaO2/FiO2, total bilirubin (TBIL), and alanine aminotransferase (ALT) levels after treatment (P < 0.05). TBIL decreased more significantly after treatment in PE+CVVHDF and PE+HP+CVVHDF groups (P < 0.01). Significant improvement in prothrombin time and albumin was observed only in PE+CVVHDF and PE+HP+CVVHDF groups (P < 0.05). The decrease of TBIL and improvement of PaO2/FiO2 ratio were more pronounced in PE+HP+CVVHDF than in HP+CVVHDF group (P < 0.05). To conclude, liver function was relatively improved by all the three combined blood purification techniques used; however, PE+HP+CVVHDF approach was found more efficient in the removal of toxic metabolites, especially bilirubin. The data suggest that the combined blood purification techniques used were effective and involved minor side effects.

Serial evaluation of children with ALF with advanced MRI, serum proinflammatory cytokines, thiamine, and cognition assessment.

OBJECTIVES: This prospective, sequential study was done to understand changes in cerebral edema (CE) on magnetic resonance imaging and magnetic resonance spectroscopy, liver functions, and neurocognitive testing (NCT) in children with acute liver failure (ALF). METHODS: A total of 11 ALF and 8 healthy controls were evaluated with advanced magnetic resonance (MR) imaging, blood proinflammatory cytokines (PCs), thiamine levels, liver functions, and NCT. Reevaluation was done at 43.5 ±â€Š26.9 days (first follow-up, n = 8) and 157.3 ±â€Š52.3 days (second follow-up, n = 6) after discharge. RESULTS: At diagnosis, patients with ALF had vasogenic and cytotoxic CE, raised brain glutamine (23.2 ±â€Š3.4 vs. 15.3 ±â€Š2.7), and serum PCs (tumor necrosis factor [TNF]-α 40.1 ±â€Š8.9 vs. 7.2 ±â€Š2.7  pg/mL, interleukin [IL]-6 29.2 ±â€Š14.4 vs. 4.7 ±â€Š1.2  pg/mL). The mammillary bodies (MBs) were smaller, and brain choline (1.9 ±â€Š0.36 vs. 2.6 ±â€Š0.6) and blood thiamine (55.2 ±â€Š6.7 vs. 81.8 ±â€Š10.2  nmol/L) were lower than controls. At first follow-up, the brain glutamine and CE recovered. Brain choline and MBs volume showed improvement and thiamine levels normalized. Significant reduction in TNF-α and IL-6 was seen. The patients performed poorly on NCT, which normalized at second follow-up. Liver biochemistry and thiamine levels were normal and TNF-α and IL-6 showed further reduction at second follow-up. CONCLUSIONS: Patients with ALF have CE contributed by raised brain glutamine and PCs. MBs are small because of thiamine deficiency and show recovery in follow-up. CE and brain glutamine recover earlier than normalization of NCT and liver functions. Persistence of raised cytokines up to 6 months after insult suggests possible contribution from liver regeneration.

Comparison of the sequential organ failure assessment score with the King's College Hospital criteria and the model for end-stage liver disease score for the prognosis of acetaminophen-induced acute liver failure.

Acetaminophen-induced acute liver failure (ALF) is a complex multiorgan illness. An assessment of the prognosis is essential for the accurate identification of patients for whom survival without liver transplantation (LT) is unlikely. The aims of this study were the comparison of prognostic models [King's College Hospital (KCH), Model for End-Stage Liver Disease, Sequential Organ Failure Assessment (SOFA), and Acute Physiology and Chronic Health Evaluation II (APACHE II)] and the identification of independent prognostic indicators of outcome. We evaluated consecutive patients with severe acetaminophen-induced ALF who were admitted to the intensive care unit. At admission, demographic, clinical, and laboratory parameters were recorded. The discriminative ability of each prognostic score at the baseline was evaluated with the area under the receiver operating characteristic curve (AUC). In addition, using a multiple logistic regression, we assessed independent factors associated with outcome. In all, 125 consecutive patients with acetaminophen-induced ALF were evaluated: 67 patients (54%) survived with conservative medical management (group 1), and 58 patients (46%) either died without LT (28%) or underwent LT (18%; group 2). Group 1 patients had significantly lower median APACHE II (10 versus 14) and SOFA scores (9 versus 12) than group 2 patients (P < 0.001). The independent indicators associated with death or LT were a longer prothrombin time (P = 0.007), the inspiratory oxygen concentration (P = 0.005), and the lactate level at 12 hours (P < 0.001). The KCH criteria had the highest specificity (83%) but the lowest sensitivity (47%), and the SOFA score had the best discriminative ability (AUC = 0.79). In conclusion, for patients with acetaminophen-induced ALF, the SOFA score performed better than the other prognostic scores, and this reflected the presence of multiorgan dysfunction. A further evaluation of SOFA with the KCH criteria is warranted.

An experimental large animal model for the assessment of bioartificial liver support systems in fulminant hepatic failure.

BACKGROUND: Pre-clinical assessment of bioartificial liver support systems requires a highly reproducible large animal model. The main objective of the present study was to develop a valid large animal model for assessing novel bioartificial liver support systems in fulminant hepatic failure. METHODS: A complete liver devascularization procedure was performed in 10 female pigs weighing 25-38 kg. Five matched pigs were sham-operated and served as controls. RESULTS: Pigs with fulminant hepatic failure developed a hyperdynamic circulation, with increased cardiac index (P(GT) < .0001), decreased systemic vascular resistance index (P(GT) < .0001) and mean arterial pressure (P(GT) = .001). Furthermore, intracranial hypertension developed (P(GT) < .0001). with increased common carotid artery flow (P(GT) < .0001) and decreased common carotid resistance (P(G) = .003). Femoral artery flow increased (P = .036). while hindleg resistance (P < .001) and renal artery resistance decreased (P = .019). Oxygen consumption (P(GT) = .050) and oxygen extraction ratio (P(GT) = .001) increased compared to controls. Arterial ammonia, venous aspartate aminotransferase and bilirubin levels increased (P(GT) < .0001, respectively). Abnormal haemostasis developed with significant loss of platelets (P(GT) = .010), decreasing fibrinogen levels (P(G) = .001) and increasing international normalized ratio (P(GT) = .012) and activated clotting time (PGT < .001). Urine became hypo-osmotic (P < .001. P(G) = .011), with decreased sodium levels (P = .08) and increased potassium levels (P(G) = .025). CONCLUSIONS: This study characterizes a reproducible large animal model for fulminant hepatic failure that seems suitable for the assessment of bioartificial liver support systems.

The value of plasma acetaminophen half-life in antidote-treated acetaminophen overdosage.

BACKGROUND: A plasma acetaminophen (INN, paracetamol) half-life of more than 4 hours has been correlated with hepatotoxicity in acetaminophen overdosing not treated with an antidote. Acetaminophen half-life has not been studied in patients receiving the antidote N -acetylcysteine. METHODS: Prospectively, 112 patients with acetaminophen overdosage all treated with intravenous N -acetylcysteine were studied. A minimum of 2 plasma acetaminophen values >20 micromol/L were available for calculation of acetaminophen half-life, assuming first-order kinetics. RESULTS: Overall, the median acetaminophen half-life was 5.4 hours (range, 0.8-119.7 hours). Forty-eight patients with no or little hepatotoxicity (ALT <1000 U/L), 43 patients with hepatotoxicity without encephalopathy, and 21 patients with hepatotoxicity and encephalopathy had acetaminophen half-lives of 3.0 hours (range, 0.8-10.0 hours), 6.4 hours (range, 1.3-19.0 hours), and 18.4 hours (range, 4.6-119.7 hours), respectively (P <.001). An acetaminophen half-life >4 hours was observed in 71 patients, and 56 of those (79%) had hepatotoxicity (ALT >1000 U/L or coma). Thirty-three of 41 patients (81%) with an acetaminophen half-life <4 hours had no hepatotoxicity. A receiver operating characteristic curve analysis showed that an acetaminophen half-life of 5.5 hours provided better discrimination; hepatotoxicity was therefore present in 49 of 54 patients with an acetaminophen half-life >5.5 hours (positive predictive value, 91%) and in 15 of 58 patients with a half-life below this limit (negative predictive value, 74%) despite treatment with N -acetylcysteine. CONCLUSIONS: Acetaminophen half-life correlates well with the degree of liver damage in patients treated with the antidote N-acetylcysteine. Longer half-lives reflect a greater toxic effect on the liver.

Caffeine test assessment for measuring liver function in critically ill patients.

Caffeine elimination was studied in 73 patients admitted to an intensive care unit, 33 of whom had liver disease. Mean plasma clearance of caffeine in patients with no liver disease (1.30 +/- 0.79 ml/kg/min) was significantly higher than in patients with liver disease (0.39 +/- 0.23 ml/kg/min). Mean half-life of caffeine in patients with liver disease (23.96 +/- 12.19 h) was significantly higher than in patients with no liver disease (7.25 +/- 3.04 h). No significant differences in distribution volumes were found. Receptor-operator curves (ROC) for plasma clearance and the half-life of elimination of caffeine showed a high diagnostic value. Therefore, the parameters for caffeine biotransformation, i.e. Cl and t1/2, are useful for assessing liver function in the population studied.