百草枯所致大鼠弥漫性肺损伤的病理特点

作者选用ＳＤ大鼠进行腹腔内一次性注入百草枯２５ｍｇ／ｋｇ后，在７个不同时间点观察其肺病理组织和超微结构改变。结果显示：百草枯可引起弥漫性毛细血管内皮细胞和肺泡１型上皮细胞为主的整层气一血屏障结构的损害，主要表现为肺泡水肿、出血、透明膜形成和（或）程度不等的肺泡炎，当损伤不能完全修复时则局部终结为纤维化。     

Immunohistochemical localization and dynamics of paraquat in the stomach and esophagus of rats

Summary The dynamics of paraquat in the stomach and esophagus of rats were demonstrated using immunohistochemical techniques. The Rats were killed 3 h, 12 h, 24 h, 3 days, 7 days and 10 days after intravenous administration of paraquat. In the stomach, paraquat was localized in the epithelial cells between 24h and 10 days after injection, whereas in the esophagus, paraquat was localized in epithelial cells and the lamina propria mucosa between 12 h and 10 days after administration. Although these findings were similar to those observed in the intestine of rats, no clear changes in the distribution of paraquat with time were observed; suggesting that the stomach and esophagus are important reservoirs for the redistribution of paraquat.     

Determination of diquat in biological materials by electron spin resonance spectroscopy

Summary An electron spin resonance (ESR) method already in use for the quantitative analysis of paraquat was applied to the analysis of diquat in blood, serum, urine, tissue homogenates and several drinks without purification of the samples. The diquat radical produced with ascorbic acid at alkaline pH was much more stable than that produced with the commonly used sodium dithionite. Radical decay in solutions covered with n-hexane was less than 5% after 60 min over a wide range of ascorbic acid concentrations. In 0.2N NaOH solution 85% of the radicals was present even after 24h. The limit of detection was 0.3 g/ml and the required amount of sample was 0.1 ml. When both diquat and paraquat were present in a sample the diquat was first extracted with 1-butanol prior to the ESR measurement, because both species were converted to the radicals.     

百草枯致眼烧伤的临床特点及治疗体会

目的 探讨百草枯致眼烧伤的临床特点及治疗方法.方法 对2008年6月至2010年5月的百草枯致眼烧伤患者5例,观察其临床表现,并给予急症冲洗,抗生素滴眼液、自家血清、肝素滴眼液及重组牛碱性成纤维细胞生长因子眼用凝胶点眼,撕除假膜及羊膜移植治疗,观察治疗效果.结果 5例百草枯烧伤患者均出现特征性的结膜假膜,假膜撕除3～4次后逐渐消失,治疗二周左右,患者角膜上皮完整,结膜面未见假膜.结论 百草枯致眼烧伤是一种以假膜形成为特征的烧伤,常规眼烧伤治疗结合撕除假膜、羊膜移植能很好的治疗本病.     

血必净联合甲强龙治疗百草枯中毒患者肺损伤的研究

目的评价血必净联合甲强龙治疗百草枯中毒患者肺损伤的临床疗效。方法选择我院急诊2004年1月-2008年9月收治的急性百草枯中毒患者51例,随机分为对照组(24例)与治疗组(27例)。对照组给予常规治疗。治疗组在对照组的基础上应用血必净注射液50mL,2次/d,连用7d;甲强龙500mg,1次/d,连用5d。结果治疗组发生低氧血症、Ⅰ型呼吸衰竭、ALI、ARDS、机械通气例数少于对照组,P<0.05;治疗组肺纹理增强、点片状影、磨玻璃影、胸腔积液、纤维条索、网状影、结节影表现明显少于对照组,P<0.05;治疗组入院后发生MODS、死亡数少于对照组,P<0.05。结论血必净联合大剂量甲强龙治疗可减轻肺组织损伤程度,降低患者死亡率。     

尿百草枯与动脉血乳酸浓度对急性百草枯中毒的预后评估

目的：观察急性百草枯中毒（APP）患者入院时尿百草枯（PQ）浓度与动脉血乳酸（Lac）浓度变化,探讨APP 患者预后特异度和敏感度较高的监测指标。方法收集我院急诊内科2012年1月－2015年1月 APP 患者142例的临床资料,根据中毒后30 d 是否死亡分为死亡组与存活组,记录入院时尿 PQ 浓度和血 Lac 浓度,通过 ROC 曲线评估其对 APP 预后的诊断价值。结果死亡组患者入院时尿 PQ 浓度和血 Lac 浓度明显高于存活组（P ＜0．05）;两者对 APP 患者死亡预测的 ROC 曲线下面积（AUC）显示,尿 PQ 浓度的 AUC 为0．843,截断值为50．12 mg／L,敏感度为78．6％,特异度为88．5％,Youden 指数0．671;血 Lac 浓度的 AUC 为0．782,截断值为3．76 mmol／L,敏感度为85．4％,特异度为76．7％,Youden 指数0．621。结论入院时尿 PQ 浓度（≥50．12 mg／L）和（或）血 Lac 浓度（≥3．76 mmol／L）可作为预测 APP 患者预后的参考指标。     

Correlation between lipid peroxidation and morphological manifestation of paraquat-induced lung injury in rats

Biochemical and morphological studies of rat lung were performed to determine the role of lipid peroxidation in the in vivo lung toxicity of paraquat. Two injections of 20 mg/kg paraquat were administered intraperitoneally every other day. While notable epithelial damage in the lungs was observed on the day after the second paraquat injection and progressed through the 5th day, the concentration of lipid peroxides in the rat lungs did not increase by the 3rd day after the injection. The lipid peroxide concentrations increased after the 5th day post-injection, and reached the maximum concentrations on the 7th day, when the damaged alveolar surface had been mostly repaired by regenerative pneumocytes. On the other hand, the delayed increase of lung lipid peroxides in paraquattreated rats paralleled the increased number of macrophages in the lung, which reached maximum numbers on the 7th day. Glutathione peroxidase activity in the lungs also increased with a similar time course. Macrophages from the lungs contained a large amount of engulfed degradation products and cellular debris, and immunohistochemical study showed high glutathione peroxidase content on the 5th and 7th days. These results suggest that lipid peroxidation is a relatively late event in the in vivo paraquat-treated lung and that the delayed increase of lipid peroxides in the lungs occurs from the phagocytic activities of macrophages rather than from toxic cell injury.     

辅助性T细胞17活化在百草枯致小鼠肺纤维化模型中的作用

目的 观察辅助性T细胞17(Th17)活化在百草枯致小鼠肺纤维化模型中的作用.方法 将30只C57BL/6小鼠随机分为对照组(10只)和百草枯中毒组(20只).百草枯中毒组经腹腔注射百草枯35 mg/kg建立小鼠中毒模型;对照组经腹腔注入等体积生理盐水.观察2组小鼠肺脏组织病理变化情况及肺纤维化评分,检测外周血Th17细胞、肺组织中维甲酸相关核孤儿受体γt(RORγt)基因及蛋白的表达情况.结果 百草枯中毒组肺平均内衬间隔、肺泡腔与肺总面积比高于对照组,平均肺泡数低于对照组,外周血Th17细胞阳性率高于对照组,肺组织中ROR-γtmRNA和蛋白表达水平高于对照组(P＜0.01).结论 百草枯致小鼠肺纤维化模型外周血及肺组织中Th17细胞明显活化,提示Th17细胞活化在百草枯致肺纤维化过程中起着重要作用.     

百草枯致神经细胞凋亡与帕金森病的相关性

帕金森病（Parkinson’s disease,PD）是一种以黑质纹状体中多巴胺能神经元选择性丢失为特征的神经变性疾病,其发病原因至今不详。多年来,遗传因素和环境因素一直是PD发病机制中研究争论的热点,然而,自发性的PD缺乏遗传因素的迹象,使环境因素在PD的病因学中占据主导地位。百草枯（Paraquat,PQ）是一种与1-甲基-4-苯基-1,2,3,6-四氢吡啶（1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine,MPTP）的活性代谢物1-甲基-4-苯基-吡啶（1-methyl-4-phenylpyridinium,MPP＋）结构相似的化学物质,而MPP＋可诱导神经细胞发生毒性改变,促进神经细胞凋亡的发生。目前,有大量文献报道,农业生产中经常使用的除草剂PQ是PD发病的危险因素之一。本文通过探讨PQ诱导SH-SY5Y细胞模型与PQ导致PD发病机制的相关性,以期进一步阐明PQ的致病机制是通过类似于MPP＋诱导细胞凋亡还是通过引起胞内氧化应激的发生或是线粒体功能障碍、蛋白酶体异常等实现的,对临床进一步预防和治疗PD具有重要意义。     

动脉血乳酸及碱剩余对百草枯中毒预后的预测价值

目的 研究百草枯中毒患者动脉血乳酸及碱剩余的变化对预后的早期预测价值.方法 75例百草枯中毒患者分为3组,入院24h内死亡者为猝死组(10例);入院24h后死亡者为近期死亡组(31例);存活组34例;分别于入院时和入院后24 h测定动脉血乳酸及碱剩余.结果 入院时猝死组乳酸水平高于近期死亡组及存活组,差异有统计学意义(P＜0.01);近期死亡组乳酸水平与存活组比较,差异无统计学意义(P=0.309).入院时猝死组碱剩余水平低于近期死亡组及存活组,近期死亡组低于存活组,差异均有统计学意义(P＜0.01,P＜0.05).入院后24 h近期死亡组乳酸水平明显高于存活组,碱剩余水平明显低于存活组,差异均有统计学意义(P＜0.01).各指标与预后的Logistic回归分析均有统计学意义(P＜0.01).入院时乳酸和碱剩余对死亡预测的ROC曲线下面积(AUC)分别是0.692和0.787,分界值为3.25和-1.75 mmol/L;对猝死预测的AUC分别是0.995和1,分界值为7.1和-12.8 mmol/L.入院后24 h乳酸和碱剩余对死亡预测的AUC分别是0.743和0.822,分界值为2.15和-5.55 mmol/L.结论 动脉血乳酸及碱剩余水平对急性百草枯中毒患者的死亡,尤其是猝死具有一定的预测价值.