A prospective observational study of a novel 2-phase infusion protocol for the administration of acetylcysteine in paracetamol poisoning

Context: The current 3-phase acetylcysteine infusion for paracetamol poisoning delivers half the dose over 15–60 min and frequently results in adverse reactions. Objective: We aimed to determine adverse reaction frequency with a modified 2-phase infusion protocol with a longer initial infusion. Materials and methods: A prospective observational study of a modified 2-phase acetylcysteine protocol was undertaken at two hospitals. Acetylcysteine was commenced on admission and ceased if paracetamol concentrations were low-risk (below the nomogram line). The first infusion was 200?mg/kg over 4–9 h based on ingestion time or 4 h for staggered/chronic ingestions. The second infusion was 100?mg/kg over 16 h. Pre-defined outcomes were frequency of adverse reactions (systemic hypersensitivity reactions or gastrointestinal); proportion with alanine transaminase (ALT)?>?1000 U/L or abnormal ALT. Results: 654 paracetamol poisonings were treated with the new protocol; median age 29 y (15–98 y); 453 females; 576 acute and 78 staggered/chronic ingestions. In 420 (64%) acetylcysteine was stopped for low-risk paracetamol concentrations. An adverse reaction occurred in 229/654 admissions (35%; 95% CI: 31–39%): 173 (26.5%; 95% CI: 23–30%) only gastrointestinal, 50 (8%; 95% CI: 6–10%) skin only systemic hypersensitivity reactions; and three severe anaphylaxis (0.5%; 95% CI: 0.1–1.5%; all hypotension). Adverse reactions occurred in 111/231 (48%) receiving full treatment compared to 116/420 (28%) in whom the infusion was stopped early (absolute difference 20%; 95% CI: 13–28%; p?<?0.0001). In 200 overdoses?<?10 g, one had toxic paracetamol concentrations, but 53 developed reactions. Sixteen patients had an ALT?>?1000 U/L and 24 an abnormal ALT attributable to paracetamol; all but one had treatment commenced?>12 h post-ingestion. Conclusion: A 2-phase acetylcysteine infusion protocol results in a fewer reactions in patients with toxic paracetamol concentrations, but is not justified in patients with low-risk paracetamol concentrations.     

Efficiency of combined methotrexate/chloroquine therapy in adjuvant-induced arthritis

The present study evaluates the effects of methotrexate (MTX) and chloroquine (CQ), and of combined MTX + CQ treatment, on the inflammatory response and on plasma and liver phosphatase and transaminase activities, employing an adjuvant-induced arthritis model in rats. Arthritis was induced by the intradermal injection of a suspension of Mycobacterium tuberculosis in mineral oil into the plantar surface of the hind paws. Development of the inflammatory response was assessed over a 21-day period. Animal groups received either: (i) MTX, administered i.p., weekly, in 0.15, 1.5, 3, 6 or 12 mg/kg doses; (ii) CQ, given intragastrically, in daily 25 or 50 mg/kg doses; or (iii) MTX + CQ, administered in two combinations (MTX1.5 mg/kg + CQ50 mg/kg, or MTX6 mg/kg + CQ50 mg/kg). At the end of the experimental period, the animals were anesthetized and killed, blood and liver samples were collected and prepared for measurement of acid and alkaline phosphatase (AP, ALP), and aspartate (AST) and alanine aminotransferase (ALT) activities. MTX at 6 and 12 mg/kg reduced the inflammatory response while CQ had no effect. MTX6 mg/kg + CQ50 mg/kg reduced the inflammatory response similar to MTX12 mg/kg, without affecting the bone marrow. Plasma AP and liver ALP activities were very elevated in the arthritic rats. While MTX treatment partially reduced both plasma AP and liver ALP activities at all doses used in the arthritic rats, CQ treatment reduced plasma AP, but increased liver AP activity. MTX + CQ treatment decreased plasma AP and liver ALP activities in the arthritic rats to control values. Plasma and liver AST activities were unaltered in the arthritic rats, and were unaffected by treatment. However, plasma and liver ALT activities were significantly reduced in the arthritic rats. While MTX or CQ treatment did not alter plasma transaminase activity in the arthritic rats, after MTX + CQ treatment, plasma ALT activity returned to normal values. In conclusion, the present data suggest that MTX + CQ treatment provides more effective anti-inflammatory protection against adjuvant-induced arthritis than does MTX alone, reverting the alterations in enzyme activities induced by this inflammatory disease in rats.     

免疫检查点抑制剂治疗的肝脏毒性管理

免疫检查点抑制剂（immune checkpoint inhibitors，ICIs）在肿瘤领域取得了令人瞩目的疗效，使肿瘤治疗进入免疫治疗的新时代。但随着ICIs的广泛使用，免疫相关不良事件（immune-related adverse events，irAEs）也随之而来。肝脏是人体重要的代谢和消化器官，ICIs引起的肝脏不良事件应引起临床医师的关注。早发现、早诊断、规范治疗是改善预后的关键。本文简述irAEs的发病现状和可能机制，对现有的免疫相关肝脏毒性管理进行总结。     

3,4-Methylenedioxymethamphetamine (ecstasy)-induced hepatotoxicity: effect on cytosolic calcium signals in isolated hepatocytes

Abstract: Aims/Background: Hepatocellular damage has been reported as a consequence of 3,4-methylenedioxymethamphetamine (MDMA) intake. However, little is known about the cellular mechanisms involved. The present study was undertaken to evaluate the effects of MDMA on cell viability as well as free calcium levels ([Ca²⁺]_i) in short-term cultured hepatocytes. Reduced glutathione (GSH), adenosine-5′-triphosphate (ATP) and lipid peroxidation were investigated to evaluate the toxic effect of MDMA, in vitro, using freshly isolated rat hepatocytes. Methods: In order to measure cytosolic free Ca²⁺ concentrations ([Ca²⁺]_i), rat hepatocytes were loaded with the Ca²⁺ indicator fura-2-acetoxymethylester (fura-2-AM). Results: A sustained rise of ([Ca²⁺]_i) after incubation with MDMA was the most noteworthy finding. In Ca²⁺-free medium, MDMA caused a reduced increase of ([Ca²⁺]_i). On the other hand, MDMA (0.1–5 mM) induced a concentration-dependent and time exposure-dependent GSH and ATP depletion. Although it did not reach statistical significance, GSH deficits were accompanied by a tendency to increase lipid peroxidation 3 h after MDMA incubation. Conclusions: The above data suggest that the marked rise of ([Ca²⁺]_i) and subsequent ATP and GSH depletion can lead to a rapid decrease in cell viability.     

Resveratrol and liver disease: from bench to bedside and community

Liver diseases incorporate several maladies, which can range from benign histological changes to serious life‐threatening conditions. These may include inborn metabolic disease, primary and metastatic cancers, alcoholic cirrhosis, viral hepatitis and drug‐induced hepatotoxicity. Liver disease remains a major cause of morbidity and mortality with significant economic and social costs. Several novel approaches are currently being studied which may provide a better therapeutic outcome. The use of naturally occurring phytochemicals, some of them obtained from dietary sources, in the amelioration of illness have recently gained considerable popularity. These agents, having anti‐oxidant and anti‐inflammatory properties, provide a safe and effective means of ameliorating chronic disease. Resveratrol, a grape polyphenol, has shown considerable promise as a therapeutic agent in the treatment of the aforementioned liver ailments. Several studies have highlighted the hepatoprotective properties of resveratrol. Resveratrol has been shown to prevent hepatic damage because of free radicals and inflammatory cytokines, induce anti‐oxidant enzymes and elevate glutathione content. Resveratrol has also been shown to modulate varied signal transduction pathways implicated in liver diseases. This review critically examines the current preclinical in vitro and in vivo studies on the preventive and therapeutic effects of resveratrol in liver diseases. The review highlights the pharmacological mechanisms involved in mediating the aforementioned effects. Toxicity, pharmacokinetics and clinical bioavailability of resveratrol are also reviewed in this article. The challenges involved, future directions and novel approaches such as site‐specific drug delivery in the use of resveratrol for the prevention and treatment of liver disease are also discussed.     

吴茱萸次碱对肝肾毒性的初步研究

目的:探讨吴茱萸次碱Rutecarpine(Rut)在体外对人正常肝细胞(HL7702)、人胚胎肾细胞(HEK293)的影响,采用共培养体系初步比较Rut对肝肾细胞活力的影响,并选用小鼠进行整体验证。方法:①采用MTT法检测Rut在肝肾细胞单独培养或共培养体系中对细胞活力的影响并采用倒置显微镜对细胞形态进行观察;②给予Rut后,检测肝肾细胞培养上清液中丙氨酸转氨酶(ALT),天冬氨酸转氨酶(AST),碱性磷酸酶(ALP),尿素氮(BUN),肌酐(Cr),乳酸脱氢酶(LDH)的变化;③整体实验观察静脉给予Rut对小鼠肝肾功能和组织病理学的影响。结果:①MTT法显示,2,4μg·mL-1的Rut使肝肾细胞活力均下降,且相同浓度下的Rut对肝细胞的抑制作用大于肾细胞;②4μg·mL-1的Rut使肝细胞上清液中的AST,ALP,LDH水平均升高(P<0.01);③整体实验表明,小鼠静脉给予10 mg·kg-1 Rut 7 d后,血清中的ALP水平有极显著的上升(P<0.01),ALT,AST,BUN,Cr水平只出现升高的趋势,病理学检查发现约1/3的小鼠肝脏出现肝细胞核分裂象增多,仅有1只小鼠肾脏出现嗜碱性病变。结论:大剂量Rut可能对肝肾具有一定的毒性作用,肝肾细胞共培养体系与细胞单独培养体系均可用于药物对细胞的毒性研究。     

苍耳子对大鼠肝脏毒性作用的代谢组学研究

目的:观察苍耳子对大鼠尿液代谢轮廓、整体表征和血液生化指标等的影响,探讨代谢组学方法在中药毒性评价中的作用.方法:用随机数字表法将30只雄性Wistar大鼠分为苍耳子低剂量组、高剂量组和对照组,每组10只.苍耳子低剂量和高剂量组大鼠分别经灌胃给予一定容量的含苍耳子水提取液(相当于生药1.05和21.0 g/kg),1次/d,共28 d;对照组给予同体积0.9％氯化钠溶液.给药期间观察大鼠体重、被毛、运动及精神状态的改变;给药前和给药7、14、21、28d检测血清丙氨酸转氨酶(ALT)和天冬氨酸转氨酶(AST)水平,收集24h尿液,用超高效液相色谱/飞行时间质谱方法测定大鼠尿液代谢轮廓和整体表征.结果:苍耳子高剂量组大鼠在给药期间陆续出现被毛光泽度下降、脱毛、活动量和摄食量减少、反应迟钝等现象.苍耳子低剂量组仅2只大鼠在给药28d后表现为少动喜卧,被毛光泽度下降.苍耳子高剂量组大鼠给药21和28 d时体重均明显低于苍耳子低剂量组(P＜0.05)和对照组(P＜0.01),苍耳子低剂量组与对照组大鼠体重在各时间段的差异均无统计学意义(均P＞0.05).苍耳子高剂量组大鼠给药21 d时的ALT、AST水平[(42.9±3.9)U/L、(107.9±12.7) U/L]明显高于低剂量组[ (33.8 ±4.4) U/L、(95.8±16.6)U/L]和对照组[(31.8±4.4) U/L、(93.5±15.8) U/L],差异均有统计学意义(均P＜0.05),给药28 d时苍耳子高剂量组血清ALT、AST水平达峰值.苍耳子低剂量组不同给药时间血清ALT、AST水平与对照组比较差异均无统计学意义(均P＞0.05).苍耳子高剂量组给药第7、14、21、28天24h尿液代谢物表型的聚类分布均偏离对照组,且随给药时间的延长而增大.苍耳子低剂量组给药第7、14、21天24h尿液代谢物表型的聚类分布位于对照组附近且与对照组有部分重叠,给药28 d时出现单独聚类.结论:用代谢组学方法检测苍耳子肝毒性灵敏度较高,可用于评价中药的毒性反应.     

益肾乌发口服液对小鼠急性肝毒性"量-时-毒"关系研究

目的 研究益肾乌发口服液单次给药致小鼠急性肝毒性的"量-时-毒"关系.方法 "时-毒"关系研究:小鼠灌胃一定剂量的益肾乌发口服液,分别于给药后不同时间检测血清丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)、总胆红素(TBI)水平及肝、脾、胸腺等脏器指数的变化."量-毒"关系研究:给小鼠灌胃不同剂量的益肾乌发口服液,于给药后2h按"时-毒"研究方法对小鼠进行相应处理.结果 小鼠血清ALT、AST、TBI水平均在灌胃较高剂量的益肾乌发口服液后2h达到高峰,给药后12h肝脏指数升至最高,给药后72h可恢复至正常值;剂量在(4.46～25)mL·kg-1之间肝脏可产生明显病理损伤,且随着剂量增大,ALT、AST、TBI水平升高显著.结论 小鼠单次灌胃一定剂量的益肾乌发口服液可造成急性肝毒性损伤,并呈现明显的"量-时-毒"关系.     

781例肺结核患者药物致肝损害的相关因素分析

目的分析抗结核药物致肝损害可能的危险因素,为指导临床抗结核药物的使用、减少药物性肝损害以及制定结核病控制的行为干预措施提供科学理论依据。方法采用历史性队列研究方法,回顾性分析2005年5月~10月的年满18周岁的初治肺结核病住院患者病例资料781例,采用非条件Logistic回归模型进行分析,筛选结核药物致肝损害的主要危险因素。结果以抗结核药物性肝损害的发生为因变量,危险因素为自变量,进行Lo-gistic逐步回归分析,最终进入模型的因素有饮酒、营养、HBsAg、性别和年龄。结论饮酒、营养不良、HBsAg（＋）、高龄和男性是抗结核药物致肝损害的主要危险因素,治疗同时定期监测肝功能变化有助于减少肝损害的发生。     

香豆素类化合物药理和毒理作用的研究进展

香豆素类化合物是自然界重要的一类天然有机化合物,存在于不同种属的植物中,具有广泛的用途。实验研究发现香豆素具有抗HIV、抗肿瘤、抗氧化、抗炎等多种药理活性,在临床上广泛用于抗凝血和淋巴管性水肿的治疗。近年来的研究发现,香豆素类化合物在啮齿类动物中存在着明显的毒性作用,且具有种属和位点特异性,这与其代谢途径和CYP2A6酶的多态性有关。另外,毒性作用还与给药剂量和给药途径密切相关,口服和高剂量给药更容易产生毒性反应。该文综述了近年来有关香豆素及其衍生物在药理和毒理方面的研究进展,以期为香豆素类化合物的研发和临床应用提供帮助。