实验性急性肝衰竭大鼠TNF-α和IFN-γ/IL4的表达

目的 研究TNF-α和Th1/Th2型细胞因子(IFN-γ/IL-4)在D-氨基半乳糖/内毒素所致急性肝衰竭大鼠血清和肝、肺组织中的表达,方法取30只Wistar大鼠腹腔内注射D-氨基半乳糖/内毒素诱导大鼠急性肝衰竭模型(AHF组,n=30),于造模3、6、12、24、48、72 h各取5只检测其血清丙氨酸转氨酶(ALT),肝组织的病理形态学变化,血清巾TNF-α和IFN-γ/lL-4水平的变化,肝、肺组织内TNF-α和IFN-γ/IL-4的表达,另取30只Wistar大鼠腹腔内注射等量生理盐水为正常对照(N组,n=30).结果 AHF组各时间点血清ALT的增高和N组相比有统计学差异(P<0.05),肝内炎细胞浸润、坏死明显;AHF组血清内TNF-α 3、6 h分别为0.255±0.133、0.150±0.061,比N组相应时间点均增高(P<0.01,P<0.05);Th1型细胞因子(IFN-γ)与N组相比3、6 h均增高(P均<0.01);Th2型细胞因于(IL-4)水平在各时间点无明显变化(P>0.05);AHF组肺组织与N组相比TNF-α的表达在3、6、12 h均明显增高(P均<0.01).结论 TNF-α和IFN-γ在急性肝衰竭大鼠模型的早期阶段起重要作用;IL-4可能不参与此动物模型的病理过程;肺组织TNF-α增高与肝衰竭的关系值得探讨.     

Clozapine-induced fatal fulminant hepatic failure: A case report

Fulminant hepatic failure (FHF) refers to the rapid development of severe acute liver injury with impaired synthetic function and encephalopathy in a person who previously had a normal liver or had well-compensated liver disease. The potential causes of FHF are numerous, but viral or toxin-induced hepatitis are the most common. Clozapine-induced hepatotoxicity has rarely been reported in the literature, occurs via an unknown mechanism and results in liver biochemical abnormalities that are usually of no clinical significance. In approximately 30% to 50% of patients treated with clozapine, there is an asymptomatic rise in serum aminotransaminase levels; however, there are no current guidelines for routine monitoring of liver function tests and liver enzymes during its use. Fatal fulminant hepatitis has only been reported in three patients receiving clozapine. A case of fatal FHF that occurred in a schizophrenic woman who began clozapine therapy shortly before her illness developed is described.     

妊娠期暴发型肝功能衰竭的研究

目的探讨妊娠期暴发型肝功能衰竭(FHFP)的临床,生化,病原学特点。方法观察21例FHFP临床表现,并分析实验室资料,13例作肝组织学检查。结果乙型肝炎病毒感染7例,乙型肝炎病毒、戊型肝炎病毒重叠感染2例。FHFP血清白蛋白极显著低于妊娠期急性肝炎和慢性肝炎,分别为(25.19±6．95)、(33．17±3．44)及(33．80±3．78)g/L(均P＜0.01)。肝组织学诊断为,存活的6例中,急性肝炎1例,慢性肝炎4例,瘀胆型肝炎1例。死亡7例中,慢性肝炎4例,瘀胆型肝炎2例,产前子痫肝损害1例。结论肝炎病毒是FHFP的病因之一。低蛋白血症在FHFP发病中起着重要作用;FHFP可能是一种独特的综合征。     

A Macaca mulatta model of fulminant hepatic failure

AIM: To establish an appropriate primate model of fulminant hepatic failure (FHF).METHODS: We have, for the first time, established a large animal model of FHF in Macaca mulatta by intraperitoneal infusion of amatoxin and endotoxin. Clinical features, biochemical indexes, histopathology and iconography were examined to dynamically investigate the progress and outcome of the animal model.RESULTS: Our results showed that the enzymes and serum bilirubin were markedly increased and the enzyme-bilirubin segregation emerged 36 h after toxin administration. Coagulation activity was significantly decreased. Gradually deteriorated parenchymal abnormality was detected by magnetic resonance imaging (MRI) and ultrasonography at 48 h. The liver biopsy showed marked hepatocyte steatosis and massive parenchymal necrosis at 36 h and 49 h, respectively. The autopsy showed typical yellow atrophy of the liver. Hepatic encephalopathy of the models was also confirmed by hepatic coma, MRI and pathological changes of cerebral edema. The lethal effects of the extrahepatic organ dysfunction were ruled out by their biochemical indices, imaging and histopathology.CONCLUSION: We have established an appropriate large primate model of FHF, which is closely similar to clinic cases, and can be used for investigation of the mechanism of FHF and for evaluation of potential medical therapies.     

Antithrombin III concentrate in the treatment of fulminant hepatic failure

Twenty-six patients with fulminant hepatic failure were treated with daily infusions of antithrombin III concentrate until recovery of consciousness or death. Seven patients were alive (group A), 7 survived 17 to 47 days after treatment (group B), and 12 died within 9 days (group C). Decreased plasma antithrombin III levels increased on the day after treatment, irrespective of the pretreatment levels in all patients. Continuous or temporary normalization was seen in all patients in groups A and B, but in only 5 in group C patients whose bleeding was extensive (p<0.05). An abrupt drop in peripheral platelet counts occurred when plasma antithrombin III levels were below normal. General bleeding accompanied this drop. These results suggest that maintained normal plasma antithrombin III levels are beneficial for prolonged survival time in fulminant hepatic failure, probably through controlling intravascular coagulation, and that antithrombin III infusion may be useful for such treatment.     

Prostacyclin inhibition by indomethacin aggravates hepatic damage and encephalopathy in rats with thioacetamide-induced fulminant hepatic failure

AIM: Vasodilatation and increased capillary permeability have been proposed to be involved in the pathogenesis of acute and chronic form of hepatic encephalopathy. Prostacyclin (PGI2) and nitric oxide (NO) are important contributors to hyperdynamic circulation in portal hypertensive states. Our previous study showed that chronic inhibition of NO had detrimental effects on the severity of encephalopathy in thioacetamide (TAA)-treated rats due to aggravation of liver damage. To date, there are no detailed data concerning the effects of PGI2 inhibition on the severity of hepatic encephalopathy during fulminant hepatic failure. METHODS: Male Sprague-Dawley rats weighing 300-350 g were used. Fulminant hepatic failure was induced by intraperitoneal injection of TAA (350 mg/(kg·d) for 3 d. Rats were divided into two groups to receive intraperitoneal injection of indomethacin (5 mg/(kg·d), n = 20) or normal saline (N/S, n = 20) for 5 d, starting 2 d before TAA administration. Severity of encephalopathy was assessed by the counts of motor activity measured with Opto-Varimex animal activity meter. Plasma tumor necrosis factor-α (TNF-α, an index of liver injury) and 6-keto-PGF1α (a metabolite of PGI2) levels were measured by enzyme-linked immunosorbent assay. RESULTS: As compared with N/S-treated rats, the mortality rate was significantly higher in rats receiving indomethacin (20% vs5%, P<0.01). Inhibition of PGI2 created detrimental effects on total movement counts (indomethacin vs N/S: 438±102 vs 841±145 counts/30 min, P<0.05). Rats treated with indomethacin had significant higher plasma levels of TNPa (indomethacin vs N/S: 22±5 vs 10±1 pg/mL, P<0.05) and lower plasma levels of 6-keto-PGF1α (P<0.001), but not total bilirubin or creatinine (P>0.05), as compared with rats treated with N/S. CONCLUSION: Chronic indomethacin administration has detrimental effects on the severity of encephalopathy in TAA-treated rats and this phenomenon may be attributed to the aggravation of liver injury. This study suggests that PGI2 may provide a protective role in the development of fulminant hepatic failure.     

Increased intracranial pressure in a porcine model of fulminant hepatic failure using amatoxin and endotoxin

BACKGROUND/AIMS: The purpose of this study was to develop a clinically relevant porcine model of fulminant hepatic failure (FHF) by means of administration of amatoxin and endotoxin. METHODS: Pigs were intraportally administered only saline in group 1 (n = 3), 1 microg/kg of lipopolysaccharide (LPS) in group 2 (n = 4), 0.1 mg/kg of alpha-amanitin in group 3 (n = 5), and amanitin plus LPS in group 4 (n = 9). RESULTS: All the pigs in groups 1 and 2 survived with minimal changes in liver function tests. In contrast to the 60% mortality in group 3, all the pigs in group 4 died within 96 h, with a significant increase in aspartate transaminase at 24 h (9,757 +/- 2,167 IU/I). In addition, they demonstrated severe metabolic disorders, such as serum lactate accumulation, hypoglycemia, coagulopathy, plasma amino acid imbalance, and hyperammonemia. The intracranial pressure significantly increased to 17.8 +/- 2.5 mmHg immediately before death. Reversal of FHF in these pigs following orthotopic liver transplantation confirmed that the toxicity is liver-specific and that the graft liver is unaffected. CONCLUSIONS: This porcine model of FHF induced by a combination of amanitin and LPS will be of much use in the development of new therapies for human FHF.     

Multimodal brain monitoring in fulminant hepatic failure

Acute liver failure, also known as fulminant hepatic failure(FHF), embraces a spectrum of clinical entities characterized by acute liver injury, severe hepatocellular dysfunction, and hepatic encephalopathy. Cerebral edema and intracranial hypertension are common causes of mortality in patients with FHF. The management of patients who present acute liver failure starts with determining the cause and an initial evaluation of prognosis. Regardless of whether or not patients are listed for liver transplantation, they should still be monitored for recovery, death, or transplantation. In the past, neuromonitoring was restricted to serial clinical neurologic examination and, in some cases, intracranial pressure monitoring. Over the years, this monitoring has proven insufficient, as brain abnormalities were detected at late and irreversible stages. The need for real-time monitoring of brain functions to favor prompt treatment and avert irreversible brain injuries led to the concepts of multimodal monitoring and neurophysiological decision support. New monitoring techniques, such as brain tissue oxygen tension, continuous electroencephalogram, transcranial Doppler, and cerebral microdialysis, have been developed. These techniques enable early diagnosis of brain hemodynamic, electrical, and biochemical changes, allow brain anatomical and physiological monitoring-guided therapy, and have improved patient survival rates. The purpose of this review is to discuss the multimodality methods available for monitoring patients with FHF in the neurocritical care setting.     

组织蛋白酶B在小鼠暴发性肝衰竭肝组织中的表达

目的研究组织蛋白酶B在暴发性肝衰竭小鼠肝组织中的表达。方法雄性昆明种小鼠腹腔同时注射脂多糖和D-氨基半乳糖,动态观察给药后2、4、6、8 h肝脏病理改变;以TUNEL法检测肝细胞凋亡;应用免疫组化和RT-PCR检测肝组织中组织蛋白酶B的表达。结果肝组织病理：给药后4 h出现凋亡细胞,6 h大量肝细胞凋亡,8 h以肝细胞坏死为主;TUNEL：给药后凋亡指数逐渐升高,6 h达到高峰,8 h有所降低;免疫组化：组织蛋白酶B表达2 h无明显变化（P〉0.05）,4 h逐渐增加,8 h达到高峰（P〈0.05）;RT-PCR：2 h组织蛋白酶B mRNA的表达量无明显变化（P〉0.05）,4 h表达略有升高,6 h表达最高,8 h表达有所降低（P〈0.05）。结论组织蛋白酶B在小鼠暴发性肝衰竭肝组织中表达明显增加,提示其可能通过促进肝细胞的凋亡而参与了暴发性肝衰竭的发病。     

Brain edema and intracranial hypertension in fulminant hepatic failure＂ Pathophysiology and management

INTRODUCTION Fulminant hepatic failure (FHF) is an infrequent but dreadful disease, defined by the appearance of hepatic encephalopathy within 8 wk after the onset of jaundice in patients with no known chronic liver disease[1]. Most FHF patients rapidly d…     

小鼠暴发性肝衰竭肝细胞凋亡形态学及其调控机制

目的:研究在实验性暴发性肝衰竭(fulminant hepatic failure,FHF)中肝细胞凋亡的形态学变化以及一氧化氮(nitric oxide,NO)、Fas和Bcl-2对肝细胞凋亡的调控作用．方法:脂多糖(LPS)和D-氨基半乳糖(D-GalN)联合应用制备FHF小鼠模型;采用免疫组化方法检测肝组织Fas 及Bcl-2表达,分别采用硝酸还原酶法和RT-PCR法检测血清NO水平及肝组织iNOS mRNA表达;TUNEL法检测肝细胞凋亡;在用药后动态观察Fas及Bcl-2表达、血清NO水平及肝组织iNOS mRNA表达及肝细胞凋亡的变化,并对模型鼠给予iNOS的抑制剂L-NMMA,动态观察上述指标的变化．结果:在FHF模型小鼠中,用药后2 h开始血清NO水平及iNOs mRNA的表达即升高,于4 h达高峰;用药后2 h 开始Fas有少量表达,至8 h和12 h表达均明显增多,与 2 h组比较差异显著(100％ vs 20％,P<0．01),与4 h组比较差异也比较显著(100％ vs 40％,P<0．05)．模型组2 h Bcl-2有较多表达,4 h表达最多,4 h与2 h比较差异显著 (90％ vs 60％,P<0．05),与8,12h比较差异非常显著(90％ vs 20%,均P<0．01)．8 h可出现典型的肝细胞凋亡表现．与模型组各时间点比较,给予iNOS的抑制剂L-NMMA 后血清NO水平及iNOs mRNA的表达均为正常水平, Fas及Bcl-2表达均无显著差异(P>0．05),阻断后8 h亦可见典型的肝细胞凋亡表现,阻断NO可使病变较模型组更为严重．结论:在FHF中,Fas及Bcl-2的表达均增加,Fas的表达与肝细胞凋亡相一致,而Bcl-2的表达与肝细胞凋亡呈负相关．单纯应用NO拮抗剂对肝细胞凋亡及肝损伤无保护作用．