MacELISA、RPHI和IFAT用于流行性出血热早期诊断的比较

比较了IgM捕获ELISA(MacELISA)、反向间接血凝抑制试验(RPHI)和间接免疫荧光抗体试验(IFAT)检测流行性出血热(EHF)病人血清特异性抗体的结果。MacELISA对急性期血清IgM抗体的阳性检出率与RPHI对总抗体的阳性检出率相近,两法都具有较高的敏感性。而IFAT检测IgG抗体的阳性率则较低。总抗体滴度(RPHI)与IgG抗体滴度(IFAT)相关(r=0.542,P<0.01),而与IgM抗体滴度(MacELISA)无明显相关(r<0.1)。但进一步研究发现,3日内血清IgM抗体滴度与总抗体滴度(RPHI)存在相关关系(r=0.701,P<0.01),表明IgM抗体可能也与发病初期RPHI的较高的阳性检出率有关。本工作表明,MacELISA作为一种早期诊断方法具有高度的特异性和敏感性,而RPHI操作简便、快速、敏感性高,但存在一定的非特异性。研究还发现,流行区临床诊断为EHF的病人,IFAT(IgG)和RPHI检测均阳性,而MacELISA(IgM)阴性,提示用RPHI进行血清学诊断时,检查双份血清是必要的。     

叶片叶肉结构对环境光强的适应及对光合作用的影响

本文利用Kubelka-Munk理论描述了平行光在叶片内的吸收和散射,同时利用叶片分层光合作用非直角双曲线光反应模型,给出了整张叶片光合作用计算式。最后利用优化理论阐明了叶片叶肉分化成光合特性具有明显差异的栅栏组织和海绵组织可能是对叶片内光梯度的一种适应;同时证明了叶片叶肉在一定环境光强下存在一个最佳的栅栏组织和海绵组织比例,并且这个比例随环境光强增大而增大,这最佳比例也受叶肉组织光合特性差异的影响。     

Radiosynthesis and in vivo evaluation of [11C]MP-10 as a PET probe for imaging PDE10A in rodent and non-human primate brain

2-((4-(1-[(11)C]Methyl-4-(pyridin-4-yl)-1H-pyrazol-3-yl)phenoxy)methyl)-quinoline (MP-10), a specific PDE10A inhibitor (IC(50)=0.18 nM with 100-fold selectivity over other PDEs), was radiosynthesized by alkylation of the desmethyl precursor with [(11)C]CH(3)I, ～45% yield, >92% radiochemical purity, >370 GBq/μmol specific activity at end of bombardment (EOB). Evaluation in Sprague-Dawley rats revealed that [(11)C]MP-10 had highest brain accumulation in the PDE10A enriched-striatum, the 30 min striatum: cerebellum ratio reached 6.55. MicroPET studies of [(11)C]MP-10 in monkeys displayed selective uptake in striatum. However, a radiolabeled metabolite capable of penetrating the blood-brain-barrier may limit the clinical utility of [(11)C]MP-10 as a PDE10A PET tracer.     

一例乙型肝炎患者体内不同HBV克隆的序列差异

采用ＰＣＲ扩增、噬菌体克隆和核苷酸序列分析的方法对一例乙型肝炎患者体内ＨＢＶ的ＨＢｓＡｇ编码区和部分前Ｓ２区进行序列分析。结果发现同一患者体内获得的不同ＨＢＶＤＮＡ克隆间存在个别碱基的差异,而这种差异并非方法学本身产生的。由此得出的结论是,这种碱基“突变”反映了乙型肝炎患者体内ＨＢＶ基因组实际存在的多态性。     

半夏属 (PINELLIA)的花粉粒和醇溶蛋白比较

继细胞学 〔1〕、形态学 〔2〕和比较解剖学 〔3〕的研究之后 ,我们又对半夏属的花粉粒和醇溶蛋白作了比较分析 ,旨在探讨这些性状的变异与分类学价值。1 　材料和方法1 .1　实验材料　实验材料采自华东 3省的不同地区。在南京栽植至少 1年后 ,在盛花季节 ( 5月 )选有花植株的花粉和地下块茎作实验分析。各材料的种名、群体编号和产地见表 1。表 1 　供实验用的半夏属 5种植物群体材料的来源Table1　 Sources of material for experiment of the populationsbelonging to5species of Pinellia种名Species群体编号No.of populations产地Lo…     

Phosphorylation on tyrosine-15 of p34(Cdc2) by ErbB2 inhibits p34(Cdc2) activation and is involved in resistance to taxol-induced apoptosis

ErbB2 overexpression confers resistance to taxol-induced apoptosis by inhibiting p34(Cdc2) activation. One mechanism is via ErbB2-mediated upregulation of p21(Cip1), which inhibits Cdc2. Here, we report that the inhibitory phosphorylation on Cdc2 tyrosine (Y)15 (Cdc2-Y15-p) is elevated in ErbB2-overexpressing breast cancer cells and primary tumors. ErbB2 binds to and colocalizes with cyclin B-Cdc2 complexes and phosphorylates Cdc2-Y15. The ErbB2 kinase domain is sufficient to directly phosphorylate Cdc2-Y15. Increased Cdc2-Y15-p in ErbB2-overexpressing cells corresponds with delayed M phase entry. Expressing a nonphosphorylatable mutant of Cdc2 renders cells more sensitive to taxol-induced apoptosis. Thus, ErbB2 membrane RTK can confer resistance to taxol-induced apoptosis by directly phosphorylating Cdc2.     

Vaccination of chickens with DNA vaccine encoding Eimeria acervulina 3-1E and chicken IL-15 offers protection against homologous challenge

Eimeria acervulina 3-1E antigen gene and mature chicken interleukin 15 (mChIL-15) gene were cloned into expression vector pcDNA3.1(+) in different forms, produced DNA vaccine pcDNA3.1-3-1E, and pcDNA3.1-3-1E-linker-mChIL-15 co-expressing E. acervulina 3-1E gene and mChIL-15 gene, respectively. The expression of objective gene in vitro was detected by indirect fluorescent antibody technique and immunohistochemistry. The two DNA vaccines were administered by intramuscular leg injection. An animal challenge experiment was carried out to evaluate the immune protective efficacy of the vaccines. The results indicated that DNA vaccines were successfully constructed and the expression of objective gene could be detected in vitro. The animal experimental results showed that both DNA vaccines could provide partial protection against homologous challenge in chickens. The chimeric DNA vaccine, pcDNA3.1-3-1E-linker-mChIL-15, could significantly increase oocyst decrease ratio, reduce the average lesion score in the duodenum, improve body weight gain, and increase anti-coccidial index (ACI) compared to the DNA vaccine pcDNA3.1-3-1E. Taken together, these results demonstrate ChIL-15 enhance the immunogenicity of 3-1E DNA vaccine, and co-expression of cytokine and optimized surface antigen of Eimeria may be a promising method to enhance immunogenicity of DNA vaccines in poultry.     

Baicalein suppresses the SOS response system of Staphylococcus aureus induced by ciprofloxacin

Numerous antibiotics can induce an SOS repair system in bacteria that leads to antibiotic-resistant mutation of the bacterium. Therefore, searching for drugs that can prevent the SOS response and thus improve the long-term viability of some antibiotics is important. In this study, we aimed to detect the suppressive effects of baicalein on the SOS system and rifampin-resistant mutation in Staphylococcus aureus. We determined the reactive oxygen species (ROS) formation and intracellular ATP level in S. aureus with baicalein treatment to investigate the mechanisms involved in its effects on the SOS system. The results showed that baicalein was a potent inhibitor of the expression of the SOS genes RecA, LexA and SACOL1400. The rifampin-resistant mutation rate of S. aureus induced by ciprofloxacin was significantly reduced after treatment with baicalein. Treatment with baicalein led to a significant decrease in intracellular reactive oxygen species (ROS) formation and ATP level. Our findings indicate that baicalein may be an SOS-response inhibitor in S. aureus through inhibiting ROS formation and ATP production and may be used to prevent excessive mutation induced by antibiotics.