Binding property of rat andLimulus C-reactive proteins (CRP) to mercury

Summary The C-reactive proteins (CRP) from both rat andLimulus were found to bind mercury (Hg) in both in vivo and in vitro conditions. CRP has high-affinity binding sites for Hg as evidenced by the loss of free sulfhydryl groups, arrested mobility in polyacrylamide gel electrophoresis, and the consumption of CRP in the serum after Hg administration. The binding was tight as it could not be inhibited either by the addition of cysteine or EDTA. By using a direct titration method it was shown that binding of Hg to CRP was saturable at a molar ratio of Hg/CRP=13.11. The possibility that CRP may act as a scavenger for Hg is discussed.     

重组人肿瘤坏死因子粗提取工艺的研究

通过研究重组人肿瘤坏死因子α(rhTNF-α)的粗提取工艺中各操作条件对目标蛋白纯化的影响,发展了一条纯化rhTNF-α的集成化工艺.该工艺组合细胞破碎,热变性与硫酸铵分级沉淀,有效节省离心步骤,缩短工艺流程,所得粗提物中目标蛋白占总蛋白含量的57%,目标蛋白回收率为90.3%,活性回收率为85.8%,各项指标均比未集成的工艺有较大程度的提高.     

Cloning of murine BRI3 gene and study on its function for inducing cell death

To understand the molecular mechanism of TNFα effects, the cDNA of murine BRI3 gene was cloned from the total RNA of murine brain endothelial cells (bEnd.3) treated with hTNFα by using the suppression subtractive hybridization (SSH) and the RT-PCR method. The fusion expression vector harbouring BRI3 gene and enhanced green fluorescence protein (EGFP) thus obtained were designated as pEGFP/I3. Then pEGFP/I3 was transiently transfected into L929 cells and the fusion protein EGFP/I3 was localized in cytoplasm. It is found that the expression of EGFP/I3 could induce cell death in L929 cells detected by TUNEL method and flow cytometry. And the overexpression of Bcl-2 in L929 cells can block cell death induced by EGFP/I3, indicating that murine BRI3 gene might related to the TNFa mediated cytotoxicity.     

基于网络药理学及动物实验探讨瑞香狼毒治疗RA作用机制

为探讨瑞香狼毒(Stellera chamaejasme L.)治疗类风湿性关节炎(rheumatoid arthritis,RA)的潜在机制,利用TCMSP、PubMed及TCMID数据库和文献挖掘获得瑞香狼毒主要化学成分,利用Swiss Target Prediction、Uniprot数据库获得瑞香狼毒治疗疾病靶点,运用OMIM、GeneCards及PharmGKB数据库获取RA主要作用靶点,通过对化学成分靶点与疾病基因进行交集整合,筛选瑞香狼毒治疗RA的潜在治疗靶点.使用Cytoscape 3.6.1 软件构建“药物-活性成分-靶点-疾病”相互作用网络图,将潜在治疗靶点用DAVID软件分析预测相关的生物学过程,并通过动物实验对主要生物学过程进行验证.采用ELISA检测瑞香狼毒对RA模型大鼠血清炎症因子的影响,该研究共筛选出瑞香狼毒60个活性成分,5 017个与RA潜在治疗靶点及380个交集靶点;动物实验结果表明,瑞香狼毒可以通过抑制炎症因子肿瘤坏死因子(TNF-α)、白介素-6(IL-6)、白介素-1β(IL-1β)表达以发挥抗RA作用.该研究揭示了网络药理学预测并指导实验设计的合理性,证实瑞香狼毒可以通过抑制炎症因子以发挥抗RA作用,为瑞香狼毒治疗RA的机制研究提供依据.     

Tumor necrosis factor-α inhibits collagen synthesis in human and rat granulation tissue fibroblasts

The purpose of the study was to examine the effects of tumor necrosis factor- (TNF-) on collagen gene expression in rat and human granulation tissue fibroblast cultures. The cells were exposed to 0.1, 1, 10, or 100 ng/ml of TNF-, and the rate of collagen synthesis was measured as synthesis of protein-bound³H-hydroxyproline. Total cellular RNA was isolated from fibroblasts, and measurements of specific cellular RNAs from fibroblasts were performed by Northern blot hybridizations using³²P-labeled cDNA probes. In cultures of rat granulation tissue fibroblasts TNF- decreased³H-hydroxyproline production to about 75% of that in controls and it also decreased pro1(I) and pro1(III) collagen mRNA levels, maximally to 33% and 23% of the control levels, respectively. In cultures of human granulation tissue fibroblasts a similar inhibiting effect in the production of collagen was seen. TNF- decreased the production of³H-hydroxyproline to 56% of the control value with a dose of 100 ng/ml also having an inhibiting effect on pro1(I) collagen mRNA levels of up to 43% of the control level. However, no effect was seen on pro1(III) collagen mRNA levels.     

肝血管瘤与肝癌非延迟CT扫描的鉴别诊断

分析肝血管瘤与肝癌在一过性非延迟增强扫描的ＣＴ增强表现，并寻找它们的特点，对经穿刺活检及手术病理检查证实的３１例肝肿瘤病人的ＣＴ资料（肝血管瘤１６例，肝癌１５例）作回顾性分析，所有病人均行平扫后立即做传统团注增强扫描，描述：病灶增强的类型，病灶强化的程度，强化组织的分布，造影剂用量为１．５ｍＬ／ｋｇ体重，结果，８１％的肝血管瘤及８％的肝癌病灶可见以球关或结节状强化（Ｐ〈０．０５）。８１％的肝血管瘤     

Bcl-2家族蛋白和乙肝病毒x蛋白在肝癌组织中的表达和意义

应用免疫组织化学方法检测了34例肝癌组织及其相对应的癌旁组织,探讨了Bcl-2家族中七种基因(包括促凋亡基因Bak、Bad、Bid、Bax和Bcl-xs及抑凋亡基因Bcl-2、Bcl-w)和乙肝病毒三种抗原(包括HBsAg、HBcAg和HBxAg)在肝癌组织中的表达及意义,结果显示:在肝癌组织中HBsAg、HBcAg和HBxA的阳性率分别为58.8％、26.5％和76.5％、Bcl-2七种蛋白的阳性率分别为58.8％(Bak)、55.9％(Bad)、44.1％(Bid)、41.2％(Bax)、29.4％(Bcl-xs)、35.3％(Bcl-w)和41.2％(Bcl-2)。这七种Bcl-2蛋白的表达均位于肝癌细胞的胞浆,多呈弥漫性分布,少数阳性颗粒呈散在性分布,研究发现,Bcl-2家族中抑凋亡基因Bcl-w和Bcl-2在癌组织中表达的阳性率明显高于癌旁组织(P相似文献   

Protective effects of the PARP-1 inhibitor PJ34 in hypoxic-reoxygenated cardiomyoblasts

To clarify the role of poly(ADP-ribose)polymerase-1 (PARP-1) in myocardial ischemia-reperfusion injury, we explored some effects of PJ34, a highly specific inhibitor of this enzyme, in hypoxic-reoxygenated (HR) H9c2 cardiomyoblasts. Compared to the control, HR cells showed signs of oxidative stress, marked PARP-1 activation, NAD⁺ and ATP depletion and impaired mitochondrial activity. HR cardiomyoblasts were affected by both necrosis and apoptosis, the latter involving the nuclear translocation of apoptosis-inducing factor. In HR cardiomyoblasts treated with PJ34, oxidative stress and PARP-1 activity were decreased, and NAD⁺ and ATP depletion, as well as mitochondrial impairment, were attenuated. Above all, PJ34 treatment improved the survival of HR cells; not only was necrosis significantly diminished, but apoptosis was also reduced and shifted from a caspase-independent to a caspase-dependent pathway. These results suggest that PARP-1 modulation by a selective inhibitor such as PJ34 may represent a promising approach to limit myocardial damage due to post-ischemic reperfusion. Received 27 July 2006; accepted 26 October 2006     

血浆p16基因甲基化在原发性肝细胞癌诊断中的作用

用甲基化特异性-多聚酶链反应（MSP）方法, 检测原发性肝细胞癌（HCC）、 肝硬 化、 慢性肝炎病人及健 康人各30例的血浆DNA甲基化的p16基因. 结果显示, HCC病人血浆p16 基因甲基化率为67%, 慢性肝炎、 肝硬化及健康者未发生甲基化.     

KLF4沉默与阿霉素诱导的DNA损伤协同抑制肝癌HepG2细胞的生长

探究KLF4沉默与经不同作用浓度阿霉素处理诱导的DNA损伤对肝癌HepG2细胞增殖凋亡的影响及其作用机制.应用RNA干扰技术,采用siRNA转染HepG2细胞以沉默KLF4基因.采用MTT法检测KLF4沉默前后对HepG2细胞增殖的影响,使用流式细胞术检测KLF4沉默前后对HepG2细胞周期变化影响,应用Western blot法检测转染前后HepG2细胞中KLF4蛋白及细胞周期相关蛋白表达变化.Western blot检测到高浓度的阿霉素促进KLF4的表达,并且低浓度的阿霉素可使得细胞停滞在G2/M期,高浓度的阿霉素则使部分细胞凋亡(19.31%).将KLF4沉默后,发现细胞生长变缓,低浓度的阿霉素处理后,细胞随时间增加而出现更多的细胞凋亡;高浓度的阿霉素处理后,细胞数明显减少,更多的细胞发生凋亡(28.89%),且在KLF4沉默前后均发现低浓度阿霉素促进p53与p21表达,高浓度阿霉素抑制其表达.阿霉素诱导的DNA损伤可提高KLF4的表达,KLF4依赖于DNA损伤激活的p53促进p21的表达,进而引起G1/S期细胞周期阻滞.沉默KLF4与阿霉素诱导的DNA损伤可协同抑制肝癌细胞的增殖、促进凋亡,其在肝癌细胞 HepG2中扮演十分重要的角色.