固有免疫信号因子TRIF在肝纤维化中的表达

目的初步探讨TOLL样受体下游重要信号因子TRIF与肝纤维化发生发展的病理机制关系。方法以四氯化碳皮下注射+低蛋白高脂饮食+酒精饮料的方法复制大鼠肝纤维化模型。将SD大鼠随机分成正常对照组和模型组,在完成制备模型实验后进行取材。部分实验鼠进行心脏生理盐水和多聚甲醛灌注后,取肝脏组织制备石蜡切片,进行常规HE染色和免疫组化实验;另一部分实验鼠脱颈安乐死后,取新鲜肝组织进行电镜标本的制备和Western Blot实验检测。结果 HE染色结果显示与而正常对照组大鼠相比,模型组大鼠肝小叶结构明显破坏,肝细胞数量明显减少和肝纤维化程度等特点明显;电镜结果也显示,肝纤维化组可见大量胶原纤维沉积现象,胞质可见明显的溶解现象,在狄氏腔内,肝星状细胞的细胞核溶解,血窦内皮细胞胞质、胞核皆溶解;免疫组化模型组大鼠肝组织均显示内皮细胞、星形细胞等TRIF都有强烈高表达,并且以胞核表达为主,亦见胞质表达,而正常组呈现弱阳性表达;与正常对照组相比,模型组大鼠肝组织TRIF蛋白表达都明显升高,呈显著性差异(P<0.01),与形态学的表达特点相一致。结论 TRIF在肝纤维化中表达显著增强,说明在肝纤维化过程中,TOLL样受体明显激活,并且通过下游信号转导途径,在机体内产生一系列的免疫应答反应。通过该现象的观察,我们初步证实了TOLL样受体固有免疫信号因子TRIF在纤维化形成中起着重要的作用。     

肝癌致创伤后应激障碍的心理咨询探讨

目的:初步探索心理咨询对肝癌所致创伤后应激障碍患者的干预效果。方法:一例肝癌患者接受六次心理咨询服务。采用PTSD症状评估和生活事件症状测评量表,在咨询第一次和第六次对患者实施测评,并收集患者及家属的主观描述。结果:患者经过认知行为、放松和眼动脱敏干预后,其警觉性下降、创伤再体验次数明显减少、睡眠状况改善以及对癌症治疗的管理观念提高,三个月后对患者及家属回访显示,患者症状改善在回访期维持。结论:认知和眼动脱敏疗法对肝癌所致的创伤后应激障碍患者具有潜在的正性干预效果,未来尚需广泛的实证研究。     

NMR structure of the bank vole prion protein at 20 degrees C contains a structured loop of residues 165-171

The recent introduction of bank vole (Clethrionomys glareolus) as an additional laboratory animal for research on prion diseases revealed an important difference when compared to the mouse and the Syrian hamster, since bank voles show a high susceptibility to infection by brain homogenates from a wide range of diseased species such as sheep, goats, and humans. In this context, we determined the NMR structure of the C-terminal globular domain of the recombinant bank vole prion protein (bvPrP) [bvPrP(121-231)] at 20 °C. bvPrP(121-231) has the same overall architecture as other mammalian PrPs, with three α-helices and an antiparallel β-sheet, but it differs from PrP of the mouse and most other mammalian species in that the loop connecting the second β-strand and helix α2 is precisely defined at 20 °C. This is similar to the previously described structures of elk PrP and the designed mouse PrP (mPrP) variant mPrP[S170N,N174T](121-231), whereas Syrian hamster PrP displays a structure that is in-between these limiting cases. Studies with the newly designed variant mPrP[S170N](121-231), which contains the same loop sequence as bvPrP, now also showed that the single-amino-acid substitution S170N in mPrP is sufficient for obtaining a well-defined loop, thus providing the rationale for this local structural feature in bvPrP.     

Chemically Induced Accumulation of GAGs Delays PrPSc Clearance but Prolongs Prion Disease Incubation Time

Prion diseases are a group of fatal neurodegenerative diseases affecting humans and animals. The only identified component of the infectious prion is PrP^Sc, an aberrantly folded isoform of PrP^C. Glycosaminoglycans, which constitute the main receptor for prions on cells, play a complex role in the pathogenesis of prion diseases. For example, while agents inducing aberrant lysosomal accumulation of GAGs such as Tilorone and Quinacrine significantly reduced PrP^Sc content in scrapie-infected cells, administration of Quinacrine to prion-infected subjects did not improve their clinical status. In this study, we investigated the association of PrP^Sc with cells cultured with Tilorone. We found that while the initial incorporation of PrP^Sc was similar in the treated and untreated cells, clearance of PrP^Sc from the Tilorone-treated cells was significantly impaired. Interestingly, prolonged administration of Tilorone to mice prior to prion infection resulted in a significant delay in disease onset, concomitantly with in vivo accumulation of lysosomal GAGs. We hypothesize that GAGs may complex with newly incorporated PrP^Sc in lysosomes and further stabilize the prion protein conformation. Over-stabilized PrP^Sc molecules have been shown to comprise reduced converting activity.     

A study of neurological diseases in farmed deer in Switzerland,with emphasis on chronic wasting disease

A study of neurological diseases in farmed deer, with emphasis on chronic wasting disease, was conducted during 2 years in Switzerland. Deer breeders were asked to submit the heads of all deer at least 2 years of age, found dead or slaughtered, for examination. A complete histological examination of the brain and immunohistochemical detection of the prion protein on selected regions of the brain and lymphoid tissues were performed on 120 apparently healthy and 40 diseased animals. In a number of cases, a full necropsy was performed. Significant inflammatory and/or degenerative changes were seen in 25% of the brains. No evidence for a transmissible spongiform encephalopathy was established.     

Neuroprotection of aucubin in primary diabetic encephalopathy

Hippocampal neuronal apoptosis accompanied by impairment of cognitive function occurs in primary diabetic encephalopathy. In this study, we investigated the neuroprotective mechanism of the iridoid glycoside, aucubin, using rats (n=8). Diabetes mellitus was induced in the rats by intraperitoneal (i.p.) injection of streptozotocin (60 mg/kg body weight). After 65 d, half of the DM rats were administered aucubin (5 mg/kg; i.p.) for 15 d, yielding treatment DM A. A third group of rats received no strepto- zotocin or aucibin, and served as controls (CON). Encephalopathy was assessed using Y-maze be- havioral testing. Rats were euthanized on Day 87, and hippocampi were excised for visual (light and transmission electron microscopic) and immunochemical (Western blot; immunohistochemical) as- sessments of the CA1 subfield for apoptosis and expression of regulatory proteins Bcl-2 and Bax. Treatment responses to all the parameters examined (body weight, plasma glucose, Y-maze error rates, pyramidal cell ultrastructure, proportions of apoptotic cells, levels of expression of Bcl-2 and Bax, and survivability of neuronal cells) were identical: there were highly significant differences between DM and CON groups (P<0.001), but the effects were significantly moderated (P<0.01) in DM A compared with DM. These findings confirm the association of apoptosis with the encephalopathic effects of diabetes mellitus, and suggest a major role of the expression levels of Bcl-2 and Bax in the regulation of apop- totic cell death. All of the results suggest that aucubin could effectively inhibit apoptosis by modulating the expressions of Bcl-2 and Bax genes.     

Spongiform encephalopathy,cannibalism and Neanderthals extinction

There are paleoecological evidences that Neanderthals ate the brains of deers and goats as well that of their own deceased. This would expose each individual and the population to the risks of contracting the Creutzfeldt Jacob disease. Those who consumed the remains of infected individual’s would then contract the disease and eventually infect others. If this is the case then the Neanderthal extinction could be attributed to spongiform encephalopathy and not to the cultural supremacy of the anatomically modern man.     

中药复方保肝作用的组织化学、免疫组织化学研究

目的为观察活血化瘀类保肝中药复方对肝损伤的保肝作用,并探讨其抗肝纤维化作用机制.方法采用组织化学酶显示法和免疫组织化学方法,经图像分析系统定量测定对照组、模型组、预防组、治疗组和自然恢复组各组动物标本中琥珀酸脱氢酶,5-核苷酸酶及热休克蛋白70活性与表达程度.结果琥珀酸脱氢酶、5-核苷酸酶活性和热休克蛋白70的表达模型组与对照组比P<0.01;自然恢复组、预防组与模型组比P<0.01;治疗组与自然恢复组比P>0.05.结论活血化瘀类中药复方具有一定的保肝功效.肝星形细胞热休克蛋白70的表达是否提示细胞凋亡的发生,将有待进一步研究.     

Expression of carboxylesterase and lipase genes in rat liver cell-types

Approximately 80% of the body vitamin A is stored in liver stellate cells with in the lipid droplets as retinyl esters. In low vitamin A status or after liver injury, stellate cells are depleted of the stored retinyl esters by their hydrolysis to retinol. However, the identity of retinyl ester hydrolase(s) expressed in stellate cells is unknown. The expression of carboxylesterase and lipase genes in purified liver cell-types was investigated by real-time PCR. We found that six carboxylesterase and hepatic lipase genes were expressed in hepatocytes. Adipose triglyceride lipase was expressed in Kupffer cells, stellate cells and endothelial cells. Lipoprotein lipase expression was detected in Kupffer cells and stellate cells. As a function of stellate cell activation, expression of adipose triglyceride lipase decreased by twofold and lipoprotein lipase increased by 32-fold suggesting that it may play a role in retinol ester hydrolysis during stellate cell activation.