ctB和ureⅠ双基因融合表达及其免疫特性分析

目的：构建霍乱毒素B亚单位（CtB）和幽门螺杆菌尿素膜通道蛋白（UreⅠ）融合的原核表达质粒pET32a（＋）ctB/ure Ⅰ,并初步研究融合蛋白Ct B/Ure Ⅰ的表达特性和免疫特性.方法：PCR从pUC18 ctB中克隆ctB基因,定向在pET32a（＋）/ureⅠ的ureⅠ基因5＇端插入ctB基因,构建ctB和ure Ⅰ双基因原核表达质粒pET32a（＋）ctB/ure Ⅰ,转该质粒于E.coli BL-21（DE3）,经酶切和序列分析鉴定工程菌.IPTG诱导表达,HP-His亲和层析纯化,SDS-PAGE和Gel-Pro Analizer4分析,重组蛋白免疫BALB/c小鼠.用Western blot和ELISA分析重组蛋白的免疫特性.结果：工程菌含完整的ctB和ure Ⅰ基因,与相对应基因的序列同源性分别为100%.在22℃,1 mmol/L IPTG诱导4 h后,重组蛋白的表达占菌体总蛋白12%,亲和层析纯化后蛋白纯度为94.3%.Western blot表明重组蛋白分别能与相应的抗体反应,该蛋白免疫小鼠后能产生相应的IgG抗体.结论：成功构建了能表达CtB/Ure Ⅰ蛋白的大肠杆菌表达菌株.对融合蛋白表达和纯化后,初步证明了该重组蛋白有CtB和Ure Ⅰ的双特异反应原性和免疫原性,为研究新型幽门螺杆菌疫苗奠定了坚实的基础.     

SARS-CoV N蛋白的原核表达及其免疫原性研究

为了研究SARS-CoV病毒N蛋白基因的原核表达及其免疫原性,为进一步的研究奠定基础,我们以PCR方法在全病毒基因组文库中获得全长N基因,分别克隆到pcDNA3和pET32a载体中获得重组质粒pcDNA3-N和pET32a-N。以亲和层析方法分离纯化pET32a-N转化的BL21细菌裂解液中的重组N融合蛋白,并以ELISA方法检测pcDNA3-N质粒基因免疫小鼠诱导后血清中的特异性抗体。结果pET32a-N转化BL21细菌后可检测到重组SARS-CoVN融合蛋白表达并分离纯化,pcDNA3-N基因免疫能够诱导产生N特异的体液免疫应答。研究的结果表明,SARS-CoVN蛋白可以在原核细胞中有效表达并有良好免疫原性,可以为进一步的功能研究和血清学诊断提供条件。     

人源His-talin1原核表达载体的构建及其蛋白表达

目的克隆人源talin1 cDNA,构建其高效原核表达载体,并纯化得到高纯度His-talin1融合蛋白。方法 PCR法扩增talin1基因并连接到原核表达载体pET32a(+),筛选和测序鉴定阳性克隆。将重组质粒转化大肠杆菌BL21(DE3),经过IPTG诱导表达和亲和层析分离纯化表达产物,对纯化的蛋白进行SDS-PAGE和Western blot鉴定。结果成功扩增了2.4kb的talin1基因,构建了pET32a(+)-talin1重组质粒并在大肠杆菌中诱导表达出His-talin1融合蛋白。经SDS-PAGE和Western blot方法 ,验证了高纯度纯化的融合蛋白。结论建立了高效稳定的His-talin1表达体系,为进一步研究Talin1蛋白的结构及其与P-selectin之间的关系打下基础。     

家蝇幼虫抗菌肽Attacin基因的克隆表达及抑菌生物学活性

目的克隆家蝇幼虫Attacin抗菌肽基因,构建原核融合表达载体,建立Attacin体内抗菌活性检测系统,优化表达和纯化Attacin目的蛋白,并初步研究其抗菌生物学功能。方法以pUCm-T/Attacin重组质粒为模板,设计特异性引物,PCR扩增Attacin编码区序列,分别克隆至原核表达载体pET30a( )和pGEX-4T-1,构建原核重组质粒,转化大肠埃希菌,表达重组Attacin蛋白,并在大肠埃希菌中体内检测Attacin的抗菌活性。利用亲和层析柱纯化重组融合蛋白Attacin,SDS-PAGE进行纯度分析,琼脂糖平板抑菌试验鉴定其生物活性。结果pET30a(a )/Attacin和pGEX-4T-1/Attacin重组质粒分别转化大肠埃希菌后,以IPTG诱导表达,与未诱导对照相比,含有重组质粒的宿主菌生长受到抑制,从pET30a( )/Attacin重组质粒的表达宿主菌中未能获得His-Attacin融合蛋白,而从pGEX-4T-1/Attacin重组质粒转化菌种获得GST-Attacin融合蛋白。SDS-PAGE分析表明Attacin重组蛋白分子量与预期结果一致,琼脂糖平板抑菌试验显示重组Attacin具有抗菌活性。结论Attacin基因在原核系统中成功表达,并且纯化后具有抑菌活性,为下一步研究Attacin的生物学功能及其应用开发奠定了基础。     

可溶性DC-SIGN的表达、纯化及其生物学活性分析

目的　在大肠杆菌中表达并纯化DC SIGN融合蛋白并对该融合蛋白的抗原特异性和生物学活性进行分析。方法　以重组质粒pcDNA3 .1 DC SIGN为模板 ,进行PCR扩增出带KpnⅠ和SacⅠ酶切位点的人DC SIGN凝集素cDNA ,经相应酶切后插入原核表达载体pET 3 2a( ) ,转化大肠杆菌AD494(DE3 ) ,经IPTG诱导表达DC SIGN融合蛋白 ,用Ni2 NTA树脂对融合蛋白进行纯化 ,以Westernblot试验进行鉴定 ,通过HIV与DC SIGN的亲和实验研究融合蛋白的生物学活性。结果　酶切鉴定证实DC SIGN凝集素基因已插入原核表达载体pET 3 2a( )。重组表达质粒pET 3 2a( ) DL在大肠杆菌AD494(DE3 )中成功表达了DC SIGN融合蛋白 ,其相对分子质量 (Mr)约为 3 5× 10 3。Ni2 NTA树脂纯化后 ,融合蛋白的纯度可达 90 %以上。Westernblot试验显示DC SIGN融合蛋白与鼠抗人DC SIGN抗体有特异性免疫反应。结论　在大肠杆菌中表达DC SIGN融合蛋白 ,用亲和层析的方法对其进行初步纯化 ;HIV与DC SIGN的亲和实验表明 ,可溶性DC SIGN融合蛋白能抑制R5和X4HIV与DC SIGN受体结合     

人IκBα基因原核表达质粒的构建及TrxA/IκBα融合蛋白的制备

目的利用基因重组技术构建人IκBα基因原核表达质粒,制备TrxA/IκBα融合蛋白,以便进一步研究IκBα的生物学功能和制备相应抗体. 方法以重组质粒pGEM-T-IκBα为模板,利用PCR方法扩增出带有BamHⅠ和HindⅢ酶切位点的人IκBα基因cDNA,经相应酶切后插入原核表达载体pET-32a(+).重组表达质粒pET32a(+)-IκBα转化大肠杆菌BL21(DE3),经IPTG诱导表达TrxA/IκBα融合蛋白.Western blot试验鉴定表达蛋白.超声波破菌后采用Ni-NTA树脂对TrxA/IκBα融合蛋白进行纯化. 结果酶切鉴定证实人IκBα基因cDNA已插入原核表达载体pET-32a(+).重组表达质粒pET32a(+)-IκBα在大肠杆菌BL21(DE3)中成功地表达了TrxA/IκBα融合蛋白,其相对分子质量(Mr)约为56×103,表达量约占细菌总蛋白的25%.Western blot试验显示TrxA/IκBα融合蛋白与兔抗IκBα多克隆抗体呈特异性免疫反应.经Ni-NTA树脂纯化后,TrxA/IκBα融合蛋白的纯度可高达95%以上. 结论人IκBα基因原核表达质粒的构建及TrxA/IκBα融合蛋白的制备为进一步研究IκBα的生物学功能和制备相应抗体奠定了物质基础.     

人TLR2胞外区基因的原核表达及其抗体的制备

目的: 在原核系统中表达人Toll样受体2(TLR2)胞外区基因的融合蛋白并制备多克隆抗体.方法: 应用RT-PCR方法从人外周血单个核细胞中扩增TLR2胞外区基因, 将其克隆到表达载体pET-32a( )上构建重组原核表达质粒, 并在大肠杆菌中诱导表达, 目的融合蛋白经Ni-NTA亲和层析纯化, 用SDS-PAGE和 Western blot进行鉴定.用纯化的蛋白免疫新西兰白兔, 制备多克隆抗体, 采用Western blot对抗体进行鉴定, 并用ELISA分析抗体活性.结果: 成功构建了pET-32a( )-TLR2重组表达质粒并在大肠杆菌中进行表达, 获得了纯化重组蛋白, 重组蛋白免疫白兔后能够有效地刺激抗体产生, 并具有良好的免疫活性.结论: 成功地获得人TLR2胞外区基因的融合蛋白, 制备的多克隆抗体为进一步研究TLR2胞外区的功能和生物活性奠定基础.     

尘螨变应原Der f 6 / pET32a( +) 重组质粒构建、表达、纯化及其产物血清 IgE 结合率

目的:获得尘螨变应原第6 组分Der f 6 原核表达产物并检测其与尘螨过敏性哮喘患儿血清抗体IgE 结合率。方法:酶切质粒pET28a(+)-Der f 6 获得目的基因Der f 6,将其与pET32a(+)载体连接成质粒pET32a (+)-Der f 6,转化BL21细菌后,用异丙基硫代半乳糖苷(IPTG)诱导表达,用Ni+离子亲和层析柱纯化表达产物,用十二烷基磺酸钠鄄聚丙烯酰胺凝胶电泳(SDS-PAGE)、免疫印迹实验(Western blot)和蛋白质串联质谱(MALDI-TOF/ TOF)鉴定纯化产物。以纯化获得的产物为包被抗原建立间接ELISA 法检测尘螨过敏性哮喘患儿血清抗体反应情况。结果:成功构建了原核表达质粒pET32a (+)-Der f6,将该质粒转化E.coli BL21 诱导表达,亲和层析纯化后,SDS-PAGE 显示获得目的蛋白,Western blot 验证其能够与载体的组氨酸标签结合,质谱鉴定其Der f 6 结构一致。以此产物为包被抗原建立间接ELISA 检测尘螨过敏性哮喘患儿血清,阳性率为41.3% (19/46)。结论:成功构建了原核表达质粒pET32a (+)-Der f 6,亲和纯化获得的目的蛋白具有良好的反应原性。     

小鼠精子Sp17与IL-5融合蛋白的构建、表达及其免疫原性鉴定

目的 构建和表达小鼠精子蛋白Sp17与白介素5(IL-5)融合蛋白,并对其进行纯化和免疫原性鉴定.方法 采用PCR技术从质粒pGEM-1-IL-5中扩增IL-5基因片段,将其克隆至pET/Sp17原核表达载体中与Sp17基因融合,构建重组质粒pET/Sp17-IL-5,经酶切鉴定后转化大肠杆菌B121(DE3),IPTG诱导表达,采用Ni2+-NTA Agarose 纯化,SDS-PAGE检测、N端测序及Western blot;重组蛋白Sp17.IL-5免疫小鼠后ELISA检测小鼠血清特异性抗体.结果 成功构建小鼠精子蛋白Sp17与IL-5融合蛋白的高效表达质粒pET/Sp17-IL-5,重组工程菌pET-28a(+)-sp17-IL-5/BL21经IPTG诱导目的蛋白表达率约28%,PAGE初步测定目的蛋白相对分子量(Mr)约39 000,纯化后蛋白纯度达91%,免疫后小鼠血清中检测到特异性抗体.结论 Sp17-IL-5蛋白经基因克隆获得了较高的表达量,并初步显示了较好的免疫活性,为新型Sp17避孕疫苗的研制奠定基础.     

幽门螺杆菌UreB-Omp11融合蛋白的重组疫苗候选株构建和融合蛋白的表达、纯化及免疫学活性

目的：构建幽门螺杆菌（Hp）UreB-Ompll融合蛋白的重组疫苗候选株，在大肠杆菌中表达UreB-Ompll融合蛋白，并检测其免疫学活性。方法：用PCR方法扩增郑州分离坳菌株MEL-HP27的ureB和ompll基因并用重叠延伸PCR法获得ureB-ompl1融合基因，将融合基因ureB-ompl1插入原核表达载体pET30a（＋）、pET28a（＋）及pMAL-c2X中，筛选出合适的表达系统并进行融合蛋白的表达，采用Westernblot对表达产物进行鉴定，并用Amylose亲和层析法纯化融合蛋白，应用SDS-PAGE方法对纯化产物进行分析，纯化的融合蛋白辅以免疫佐剂皮下免疫小鼠，Westernblot对免疫小鼠血清进行检测。结果：特异PCR法、酶切鉴定并经测序分析后证实融合基因ureB—ompll克隆人表达载体pE330a（＋）、pET28a（＋）与pMAL—c2X中；重组菌TBl（pMAL-ureB—ompl1）经诱导获得了高效表达的MBP-UreB—Ompll融合蛋白，该融合蛋白可以被却免疫小鼠血清和却阳性患者血清中的相应抗体所识别，纯化后的融合蛋白纯度达90％以上。通过大肠杆菌抗原吸收法纯化免疫小鼠血清后，与纯化的融合蛋白进行杂交，结果显示在M，134000处出现特异杂交带，融合蛋白具有良好的免疫原性和免疫反应性。结论：成功地构建并筛选出了却MELHP27融合蛋白UreB-Ompl1的重组疫苗候选株TBl（pMAL-ureB—ompll），为坳蛋白质疫苗和核酸疫苗的研制奠定了基础。     

Molecular basis of phenylketonuria and related hyperphenylalaninemias: mutations and polymorphisms in the human phenylalanine hydroxylase gene.

Mutations in the human phenylalanine hydroxylase gene producing phenylketonuria or hyperphenylalaninemia have now been identified in many patients from various ethnic groups. These mutations all exhibit a high degree of association with specific restriction fragment-length polymorphism haplotypes at the PAH locus. About 50 of these mutations are single-base substitutions, including six nonsense mutations and eight splicing mutations, with the remainder being missense mutations. One splicing mutation results in a 3 amino acid in-frame insertion. Two or 3 large deletions, 2 single codon deletions, and 2 single base deletions have been found. Twelve of the missense mutations apparently result from the methylation and subsequent deamination of highly mutagenic CpG dinucleotides. Recurrent mutation has been observed at several of these sites, producing associations with different haplotypes in different populations. About half of all missense mutations have been examined by in vitro expression analysis, and a significant correlation has been observed between residual PAH activity and disease phenotype. Since continuing advances in molecular methodologies have dramatically accelerated the rate in which new mutations are being identified and characterized, this register of mutations will be updated periodically.     

Temporal and spatial localization of three germline-specific proteins in medaka.

We show that germline-specific proteins, olvas (vasa), nanos, and tdrd1 (tudor), alter their localization in the cytoplasm during germline development in the medaka (Oryzias latipes). By immunohistochemical analysis, these three germline-specific proteins were detectable on granule-like structures in the cytoplasm of migrating primordial germ cells. In the germ cells of the gonadal primordia, these granules formed a hollow area lacking these three protein components. During the sexual differentiation of the female gonads, the granules were found to be reduced in size in the germ cells undergoing cystic division and they showed a perinuclear localization in the oocytes. However, the germ cells in the male gonads retained their hollow granules during this early sex differentiation stage. We further demonstrate the differential localization of olvas, nanos, and tdrd1 on these granules during medaka germline development.     

宫颈癌及其前期病变HPV感染与基因型分布

目的了解宫颈癌及宫颈上皮内瘤变CIN患者的HPV的感染和其基因分型及主要感染型别情况。方法应用型特异PCR检测宫颈癌及其前病变的患者的HPV感染及其主要基因分型情况的分析。结果在本研究宫颈癌及宫颈上皮内瘤变患者中,宫颈癌的HPV感染率为91．0％,CINⅠ／Ⅱ／Ⅲ的HPV感染率为73．3％,主要高危型HPV基因型别依次为HPV16、HPV18、HPV58、HPV33。结论在宫颈上皮内瘤变患者中感染主要高危型HPV基因型别依次为HPV16、HPV18、HPV58、HPV33、HPV16在宫颈癌和CIN中的构成比随着宫颈病变的增加而明显增加。     

Superposition of motor programs—I. Rhythmic forearm movements in man

The so-called invariant characteristics of the elbow muscles are described. An invariant characteristic is a curve on a plot of elbow static moment vs angle. An invariant characteristic shows the elbow displacements in response to different amplitudes of load change when the subject is told not to compensate, or not to intervene voluntary to correct the deflection of the arm. If an inclination of the invariant characteristic is known, the degree of central tonic coactivation of antagonistic motoneurones can be estimated. The idea was utilized when analysing rhythmic movements (2–6 Hz) of the forearm that were carried out against a spring resistance (2–10 Nm). When the spring was suddenly switched off, the deflection of forearm rose. The subject was told not to correct the deflection and not to interrupt the swingings. The mean changes of both muscle torque and joint angle were determined in the experiments so that it was possible to estimate the inclination of the invariant characteristic used at a given frequency. Judging by the results, central tonic coactivation of elbow flexors and extensors occurs and increases to maximum as the frequency of movement increases. In addition, the reciprocal activation of antagonistic muscles is well known to occur upon execution of this movement.It can be concluded that both the reciprocal and the unidirectional central commands to antagonistic motoneurones occur simultaneously. The functional significance, as well as a scheme of superposition, of these motor commands are discussed. It is suggested that the commands are universal, i.e. the nervous system operates by using them during the performance of any movement.     

Familial eosinophilia: Clinical and laboratory results on a U.S. Kindred

We describe a five-generation kindred with familial eosinophilia (FE; MIM131400), characterized by the occurrence of sustained eosinophilia of unidentifiable cause in multiple relatives. The inheritance pattern is consistent with an autosomal dominant pattern. Among 52 related subjects studied, 19 were affected and 33 were unaffected. Ten unaffected spouses were also evaluated. Four subjects with sustained eosinophilia were diagnosed with cardiac abnormalities and two of them also had neurologic symptoms. In comparison with the unaffected or spouses, evaluation of complete blood counts showed that the affected relatives had, as expected, significantly higher white cell (P < 0.005) and absolute eosinophil counts (P < 0.001) and lower red cell counts (P < 0.05). Evaluation of serum cytokine levels (IL-5, IL-3, and granulocyte-macrophage colony-stimulating factor (GMCSF) and serology for parasitic helminth infection demonstrated no differences between the affected and unaffected individuals; no individuals studied had serologic evidence for parasitic infection. There were also no differences in anti-nuclear antibody, serum cobalamin (vitamin B₁₂) level, immunoglobulin level, leukocyte alkaline phosphatase, rheumatoid factor, HLA analysis, and stool findings for ova and parasites. Among eight affected persons who had peripheral blood or bone marrow karyotype analysis, two carried the same chromosome abnormality, a pericentric inversion of chromosome 10, inv (10) (p11.2q21.2). A gene mapping study is currently underway to study the underlying genetic mechanism(s) of this syndrome. Am. J. Med. Genet. 76:229–237, 1998. © 1998 Wiley-Liss, Inc.     

Blind source separation to enhance spectral and non-linear features of magnetoencephalogram recordings. Application to Alzheimer's disease

This work studied whether a blind source separation (BSS) and component selection procedure could increase the differences between Alzheimer's disease (AD) patients and control subjects’ spectral and non-linear features of magnetoencephalogram (MEG) recordings. MEGs were acquired with a 148-channel whole-head magnetometer from 62 subjects (36 AD patients and 26 controls), who were divided randomly into training and test sets. MEGs were decomposed using the algorithm for multiple unknown signals extraction (AMUSE). The extracted AMUSE components were characterised with two spectral – median frequency and spectral entropy (SpecEn) – and two non-linear features: Lempel-Ziv complexity (LZC) and sample entropy (SampEn). One-way analysis of variance with age as a covariate was applied to the training set to decide which components had the most significant differences between groups. Then, partial reconstructions of the MEGs were computed with these significant components. In the test set, the accuracy and area under the ROC curve (AUC) associated with each partial reconstruction of the MEGs were compared with the case where no BSS-preprocessing was applied. This preprocessing increased the AUCs between 0.013 and 0.227, while the accuracy for SpecEn, LZC and SampEn rose between 6.4% and 22.6%, improving the separation between AD patients and control subjects.     

Inhibitory Effects of Scutellaria Barbata D. Don. and Euonymus Alatus Sieb. on Aromatase Activity of Human Leiomyomal Cells

It is now well documented that a large proportion of breast tumors express their own aromatase. This intratumoral aromatase produces estrogen in situ and therefore may contribute significantly to the amount of estrogen to which the cell is exposed. Thus it is not only important that aromatase inhibitors potently inhibit the peripheral production of estrogen and eliminate the external supply of estrogen to the tumor cell, but that they in addition potently inhibit intratumoral aromatase and prevent the tumor cell from making its own estrogen within the cell. To study the inhibition of intracellular aromatase, we have examined the aromatase‐inhibiting potency of the Scutellaria barbata D. Don. (SB) and Euonymus alatus Sieb. (EA) in myometrial and leiomyomal cells which contain aromatase. We have also used human placental tissues. Although SB and EA are approximately equipotent in a cell‐free aromatase system (human placental microsomes), EA is consistently 10–30 times more potent than SB in inhibiting intracellular aromatase in myometrial and leiomyomal cells. To provide insights into the effect of SB and EA on aromatase activity in leiomyomal cells, we examined the cell lines, which is induced to differentiate toward the more transformed cell phenotype by 12‐tetradecanoylphorbal‐13‐acetate (TPA) as a protein kinase C activator and transforming growth factor‐β1 (TGF‐β1). Enzyme activity was inhibited in a time‐and dose‐dependent fashion by SB and EA and by either 1–50 nM TPA or 0.01–0.5 ng/ml TGF‐β1, with maximal responses after 2–3 h exposure.