Kynurenine aminotransferase activity in human liver: identity with human hepatic C-S lyase activity and a physiological role for this enzyme

The C-S lyase enzymes are responsible for the generation of mutagenic and cytotoxic metabolites via aberrant drug-metabolising pathways in mammalian tissues. We have examined human hepatic cytosolic, mitochondrial and microsomal fractions for evidence of C-S lyase activity. The cytosolic enzyme was purified using fast protein liquid chromatography over FFQ Sepharose, Mono P and Superose 12. An homogeneous protein (monitored by SDS-PAGE) was obtained following purification, and an 11-fold increase in C-S lyase specific activity was observed. The molecular weight of the enzyme was found to be 37 kDa in denaturing conditions, 82.3 kDa in non-denaturing conditions, and the C-S lyase activity was shown to co-purify with kynurenine aminotransferase activity when the transaminase activity of the enzyme was examined with kynurenine as the substrate.     

新生儿脑病S-100蛋白监测与预后的研究进展

目的:通过监测新生儿缺氧缺血性脑病(HIE)患儿血清中S-100蛋白含量的动态变化,建立对HIE患儿的早期科学诊断及预后评估技术指标。并探讨S-100蛋白浓度变化与病情的严重程度及转归之间的关系。方法:采用酶联免疫吸附试验、双抗体夹心法检测,对120例HIE有症状组患儿(HIE轻度症状组40例,HIE中度症状组40例,HIE重度症状组40例)和40例新生儿窒息组患儿与40例对照组健康新生儿血清S-100蛋白含量进行检测,并进行动态观察。结果:①HIE有症状组不同时期血清S-100蛋白含量均显著高于对照组(P<0.01);②新生儿窒息组不同时期的血清S-100蛋白含量也明显高于对照组(P<0.01);③HIE有症状组血清S-100蛋白含量明显高于新生儿窒息组(P<0.05)。结论:HIE有症状组患儿病情越重,其血清S-100蛋白含量则越高,提示血清S-100蛋白可作为判断HIE病情程度的客观依据和早期诊断以及预后评估HIE的主要指标。     

恶性肿瘤局部淋巴结树突状细胞免疫组化研究

本文采用S-100蛋白为免疫学标记，对34例恶性肿瘤局部淋巴结内树突状细胞进行免疫组化定量研究。结果按S-100蛋白阳性细胞数目多少分为增多（7例）、减少（20例）及正常（7例）3组，统计学分析增多组均值（164.4个/mm^2)明显高于对照组（58.3个/mm^2)；减少组均值（16.5个/mm^2)组显低于对照组；而正常组均值（69.8个/mm^2)与对照组无显著差异。     

Dose dependent effects of S-20098, a melatonin agonist,on direction of re-entrainment of rat circadian activity rhythms

The chronobiotic properties of melatonin are well documented. For example, following an 8-h phase advance of the light-dark cycle daily injections of melatonin administered at the pre-shift dark onset alter the direction of re-entrainment of rat activity rhythms. Using this 8-h phase advance paradigm, the effects of the melatonin agonist S-20098 (1 mg/kg and 3 mg/kg) on the rat circadian system were compared with those of melatonin. S-20098 altered the direction of reentrainment in the same manner as melatonin. A study using lower doses of S-20098 showed that the effect on direction of re-entrainment was dose-dependent, with 100% of rats responding at a dose of 100 µg/kg. S-20098 may, therefore, have therapeutic potential as a chronobiotic in the treatment of circadian disorders in humans.     

停跳或不停跳心脏手术对血清 S-100B蛋白表达的影响

【目的】研究心脏手术围术期血清S-100B蛋白表达及其与停跳或不停跳心肺转流方式和时间的关系。【方法】体外循环心脏手术患者23例,测转流前、转流10min、转流末、转流后24h的血清S-100B蛋白表达水平。【结果】①血清S-100B蛋白质量浓度在体外循环前后动态变化:转流前(M)为0.27μg/L,转流10min后升至0.57μg/L(P<0.01),转流末达峰值1.80μg/L(P<0.01),转流后24h降为0.22μg/L(P>0.05)。转流末的血清S-100B蛋白质量浓度与转流时间呈正相关(r=0.488,P<0.05)。②停跳组(n=6)转流前、转流10min、转流末、转流后24h平均血清S-100B蛋白质量浓度分别为(0.17±0.09)μg/L、(0.48±0.13)μg/L、(1.65±0.52)μg/L和(0.19±0.04)μg/L,不停跳组(n=6)分别为(0.26±0.14)μg/L、(0.71±0.41)μg/L、(1.59±0.84)μg/L和(0.23±0.11)μg/L,两组差别无统计学意义(P>0.05)。【结论】体外循环可导致血清S-100B蛋白表达增高,其表达水平与心肺转流时间呈正相关,但与停跳或不停跳转流方式无关。     

神经损伤蛋白质标记物在中毒性神经系统疾病中的应用前景

临床神经系统损伤的检查手段多年来主要是依靠物理学的检查方法,如核磁共振、脑螺旋CT检查、脑电图、肌电图等,但始终缺乏能反映神经系统损伤的有价值的实验室生化指标。随着一些神经组织特异蛋白的发现,这些蛋白质标记物广泛应用于各种神经损伤疾病的研究,如多发性硬化、变态反应性神经系统疾病、脑血管疾病、脑外伤疾病以及周围神经疾病等,以便找到能反映相关神经组织损伤程度、范围和预测预后的敏感和特异的生化指标。在中毒领域中的报道还较少,现综述如下。1神经损伤蛋白质标记物1.1S-100B1965年MOORE等首先在牛脑组织中发现S-100,…     

Adult-onset rod disease with abundant intranuclear rods

Summary The third case of adult-onset rod disease (nemaline myopathy) with abundant myofibrillar as well as intranuclear rods is described. The 61-year-old woman suffered from progressive weakness of proximal extremities and of the neck, mimicking polymyositis. Muscle biopsy revealed a striking myopathic pattern, with intranuclear rods occurring in 31% of the fibres. On light and electron microscopy and by immunohistochemical study, the rods differed from myofibrillar rods. The absence of -actinin in intranuclear rods suggests an enhanced readiness of actin filaments to bind to diverse proteins, instead of overproduction of -actinin as the pathogenetic basis of the rod formation.     

Establishment of a human glioma cell line bearing a homogeneously staining chromosomal region and releasing α- and β-type transforming growth factors

Summary A human glioma cell line (YKG1), which was positively identified for glial fibrillary acidic (GFA) and S-100 proteins, was established from a surgical specimen of a patient with glioblastoma. Chromosome analysis of the cells revealed a homogeneously staining region (HSR) on a marker chromosome. The assay for transforming growth factors (TGFs) in the conditioned medium of the cell line revealed that it contained high levels of - and -type TGFs, which might regulate the growth of glioblastoma and influence on the peritumoral tissues.