Beta 1-6 branching of Asn-linked oligosaccharides is directly associated with metastasis

Neoplastic transformation has been associated with a variety of structural changes in cell surface carbohydrates, most notably increased sialylation and beta 1-6-linked branching of complex-type asparagine (Asn)-linked oligosaccharides (that is, -GlcNAc beta 1-6Man alpha 1-6Man beta 1-). However, little is known about the relevant glycoproteins or how these transformation-related changes in oligosaccharide biosynthesis may affect the malignant phenotype. Here it is reported that a cell surface glycoprotein, gp 130, is a major target of increased beta 1-6-linked branching and that the expression of these oligosaccharide structures is directly related to the metastatic potential of the cells. Glycosylation mutants of a metastatic tumor cell line were selected that are deficient in both beta 1-6 GlcNAc transferase V activity and metastatic potential in situ. Moreover, induction of increased beta 1-6 branching in clones of a nonmetastatic murine mammary carcinoma correlated strongly with acquisition of metastatic potential. The results indicate that increased beta 1-6-linked branching of complex-type oligosaccharides on gp 130 may be an important feature of tumor progression related to increased metastatic potential.     

哺乳动物促卵泡素氨基酸序列特征及其单克隆抗体的制备与鉴定

为制备哺乳动物促卵泡素(FSH)单克隆抗体,比对了人类、家畜、部分野生动物、鼠类等哺乳动物FSH氨基酸序列,分析其种间同源性,结果发现,多种哺乳动物FSHβ亚基氨基酸序列的同源性高于80%,且线性抗原表位高度保守。从奶牛垂体组织扩增FSHβ亚基CDS片段,构建p ET28aFSH重组质粒,诱导表达FSH重组蛋白,免疫Balb/c小鼠,取免疫小鼠的脾细胞与SP2/0骨髓瘤细胞融合,间接ELISA法筛选阳性杂交瘤细胞孔,取效价最高孔进行克隆和亚克隆,获得1株能够分泌抗FSH的单克隆抗体细胞株,命名为B4A5。B4A5细胞株经过数次传代培养、反复冻融后生长状态良好,且能够稳定分泌抗体。采用细胞株体外培养和小鼠腹水诱生法均制备了抗FSH的单克隆抗体,其效价分别为1∶640、1∶106。分别采用Western blot和间接ELISA法鉴定单克隆抗体的结合特异性和交叉反应性,结果显示,制备的单克隆抗体与FSH反应呈阳性,与促黄体素(LH)、促甲状腺素(TSH)、促乳素(PRL)、人绒毛膜促性腺激素(h CG)均无交叉反应性。综上,获得了1株能够稳定分泌单克隆抗体的杂交瘤细胞株,其分泌的单克隆抗体可特异性结合FSH蛋白。     

胰岛素对初情期前母猪垂体细胞促性腺激素释放及生长激素分泌的影响

[目的]探讨胰岛素对猪垂体前叶细胞无血清单层培养细胞分泌促卵泡素(FSH)、促黄体素(LH)、生长激素(CH)的影响。[方法]24头140日龄、体重17 kg的母猪被分成高、中、低3个能量组,利用无血清单层培养垂体模型,并用放射免疫法测定细胞液促卵泡素、促黄体素和生长激素浓度。[结果]在不同能量水平上,胰岛素对单层无血清培养垂体细胞FSH、LH及GH释放能力的影响有显著差异(P<0.05),高能组较高,低能组较低。[结论]首次研究了在初情期前母猪体外培养垂体细胞中添加胰岛素对垂体细胞分泌激素的影响,证实代谢激素在初情期前母猪下丘脑-垂体-卵巢水平上调节生殖机能。     

Evidence for a novel thioredoxin-like catalytic property of gonadotropic hormones

It has been proposed that dithiol-disulfide interchange and oxidation-reduction reactions may play a role in hormone-induced receptor activation. Inspection of the sequences of the gonadotropic hormones revealed a homologous tetrapeptide (Cys-Gly-Pro-Cys) between the beta subunit of lutropin (LH) and the active site of thioredoxin (TD). The beta subunit of follitropin (FSH) has a similar sequence (Cys-Gly-Lys-Cys). Thioredoxin is a ubiquitous protein serving as an electron donor for ribonucleotide reductase, but it also exhibits disulfide isomerase activity. The catalytic activity of TD was assayed by its ability to reactivate reduced and denatured ribonuclease. In this assay, the purified ovine FSH and bovine LH preparations tested were approximately 60 and approximately 300 times, respectively, as active as TD on a molar basis. This heretofore unsuspected catalytic property of FSH and LH may be important in understanding their mechanism of receptor activation and signal transduction.     

二氢吡啶(Diludin)对产蛋鸡内分泌的影响

１ ０２４羽３００日龄罗曼蛋鸡随机分４组,分别饲喂二氢吡啶（Ｄｉｌｕｄｉｎ）添加量０,１００,１５０,２００ ｍｇ／ｋｇ的４种饲粮,于饲喂后第３０日和第８０日采血和屠宰,研究其对蛋鸡内分泌功能的影响。结果显 示：Ｄｉｌｕｄｉｎ均显著地提高了腺垂体和血清中ＦＳＨ,ＬＨ含量,其中垂体ＦＳＨ和ＬＨ含量随饲喂剂量提高 而增加,血清ＦＳＨ和ＬＨ含量以１５０ ｍｇ／ｋｇ组效果最佳;Ｄｉｌｕｄｉｎ提高了血清Ｔ３含量,Ｔ４差异不显著, ３０日Ｔ３随饲粮中Ｄｉｌｕｄｉｎ递增而增加,８０日１５０,２００ ｍｇ／ｋｇ组与对照组差异显著;饲粮中添加Ｄｉｌｕｄｉｎ 具有改进血清雌二醇（Ｅ２）水平,其中８０ 日 １５０,２００ ｍｇ／ｋｇ组与对照组差异显著;１５０ ｍｇ／ｋｇ Ｄｉｌｕｄｉｎ显 著提高血清中孕酮（Ｐ４）含量;饲粮中添Ｄｉｌｕｄｉｎ显著提高下丘脑和腺垂体中ｃＡＭＰ含量。     

6种石斑鱼成鱼的性腺发育、脑垂体结构以及垂体中FSHβ和LHβ细胞的免疫识别

以日本海域捕获的宝石石斑鱼(Epinephelus areolatus)、黑边石斑鱼(E.fasciatus)、赤点石斑鱼(E.akaara)、尾纹九棘鲈(Cephalopholis urodeta)、蜂巢石斑鱼(E.merra)和纹波石斑鱼(E.ongus)成鱼为对象,比较其性腺发育和脑垂体结构以及垂体中FSHβ和LHβ免疫信号的分布。结果表明:宝石石斑鱼、黑边石斑鱼、赤点石斑鱼和尾纹九棘鲈性腺发育为未成熟阶段,蜂巢石斑鱼和纹波石斑鱼性腺发育为成熟阶段。6种石斑鱼的脑垂体位于间脑腹面,由神经垂体(NH)和腺垂体(AH)组成。腺垂体从左至右进一步细分为前外侧部(RPD)、中外侧部(PPD)和中间部(PI)。在宝石石斑鱼、赤点石斑鱼和纹波石斑鱼中NH结构被PPD隔开分为上下两部分,而在黑边石斑鱼、尾纹九棘鲈和蜂巢石斑鱼中NH为一个整体。6种石斑鱼脑垂体中FSHβ和LHβ细胞的免疫信号主要分布在PPD和PI区域,且FSHβ信号强度均较LHβ强,推断在石斑鱼性腺发育成熟前后,FSHβ较LHβ重要。为石斑鱼的资源保护及人工繁殖方面提供基础生物学资料和理论依据。     

Nesfatin-1对初情期雌性大鼠促性腺激素及其mRNA表达的影响

为探究侧脑室注射Nesfatin-1对雌性大鼠促性腺激素水平及其mRNA表达的影响,对初情期前雌性大鼠的侧脑室注射Nesfatin-1,采用实时荧光定量PCR法检测促黄体素(Luteinizing hormone,LH)和促卵泡素(Folliclestimulating hormone,FSH)mRNA在垂体中的变化,采用酶联免疫分析法检测血清LH和FSH的浓度。结果表明:在初情期前的雌性大鼠中,Nesfatin-1可促进初情期启动、增加卵巢重量、血清LH水平、垂体LH mRNA和FSH mRNA的表达增加(P0.05);但Nesfatin-1对FSH水平的影响不突出,注射后15min时增加(P0.05),60min不产生影响(P0.05)。侧脑室注射Nesfatin-1后15和60min均能提高血清LH水平,15min时提高更明显(P0.05),但对FSH水平的影响不尽相同。在成年的雌性大鼠中,Nesfatin-1对LH和FSH的分泌不产生影响(P0.05)。Nesfatin-1可通过下丘脑诱导和增强初情期过渡阶段雌性大鼠LH和FSH的释放及LH、FSH mRNA的表达。     

绵羊垂体促性腺激素细胞的细胞类型以及在发情周期内的变化

本研究以绵羊发情周期内的不同时期、即黄体期,卵泡前期,卵泡后期和排卵后期的垂体组织为研究对象,利用免疫荧光单和双标记方法研究绵羊垂体促性腺激素细胞的细胞类型以及在发情周期内的变化。研究结果证明：在绵羊发情周期内,垂体促黄体激素免疫萤光单标记,促卵泡激素免疫荧光单标记和ＬＨ／ＦＳＨ免疫荧光双标记细胞的细胞阳性率之间地间无显著差异;绵羊垂体ＦＳＨ和ＬＨ分泌细胞属同一细胞类型,并且在发情周期内无明显变化     

A role for glycosylation of the alpha subunit in transduction of biological signal in glycoprotein hormones

The biological properties of recombinants of glycoprotein hormones in which the alpha and beta subunits were differentially deglycosylated have been investigated. Specific deglycosylation of the alpha subunit generated a recombinant that had more receptor-binding activity but did not produce hormone response in the target cells. The deglycosylated alpha + beta recombinant was also an antagonist of the action of the native hormone. Thus, the carbohydrates in the alpha subunit play a dominant role in the transduction of the hormone signal into the cell.     

肝硬化患者腺垂体储备功能的研究

目的：研究肝硬化患者腺垂体分泌细胞的储备功能。方法：用放免法测定１０例男性肝硬化患者行药物腺垂体兴奋试验前后的血清ＰＲＬ、ＧＨ、ＦＳＨ和ＬＨ水平。结果：兴奋腺垂体前与健康对照组比较患者血清ＧＨ增高（Ｐ〈０．０５）、ＦＳＨ降低（Ｐ〈０．０５）、ＬＨ（Ｐ〉０．０５）和ＰＲＬ（Ｐ〉０．０５）与健康对照组比较差异无显著性，兴奋后垂体激素均值明显低于健康对照组（Ｐ值分别为，Ｐ〈０．０１，Ｐ〈０．０５，Ｐ〈０     

促孕散对持久黄体和卵巢静止奶牛血清生殖激素的影响

【目的】研究促孕散对持久黄体和卵巢静止奶牛雌二醇（E2）、促卵泡素（FSH）、促黄体素（LH）和孕酮（P4）4种生殖激素的影响,探讨促孕散治疗奶牛持久黄体和卵巢静止的作用机理。【方法】用促孕散治疗奶牛持久黄体和卵巢静止,统计发情率,用酶联免疫吸附法（ELISA）检测奶牛血清中的E2、FSH、LH和P4 4种生殖激素,并与正常奶牛对比。【结果】促孕散治疗持久黄体牛发情有效率为91.67%,治疗卵巢静止牛发情有效率为88.89%。促孕散处理前,持久黄体P4水平极显著高于正常组（P＜0.01）,卵巢静止P4极显著低于正常组（P＜0.01）,而两种病型在处理前E2、FSH、LH水平与正常组差异不显著（P＞0.05）。持久黄体患牛在促孕散处理后血清中E2和FSH水平不断升高,与正常组比较差异不显著（P＞0.05）,LH水平在促孕散处理后也逐渐上升,与正常组同时达到峰值,其变化规律与正常组相似,P4水平逐渐降低,与正常组水平差异不显著（P＞0.05）。卵巢静止组在促孕散处理后血清中E2、FSH和LH水平均升高,其变化规律与正常组相似,P4水平出现先升高后降低的变化,变化规律与正常组相似,差异不显著（P＞0.05）。【结论】促孕散对持久黄体和卵巢静止奶牛血清生殖激素具有显著调节和诱导发情的作用。     

广西沼泽型母水牛发情淡季生殖激素的变化规律研究

[目的]研究发情淡季母水牛生殖激素的变化规律及各激素之间的相互关系。[方法]采用酶联免疫分析方法(ELISA)测定了发情淡季广西沼泽母水牛血样中促卵泡素(FSH)、促黄体素(LH)、抑制素(INH)、雌二醇(E2)和孕酮(P4)的浓度变化,并结合B超技术检测了母水牛卵泡在发情周期中的变化。[结果]广西沼泽型母水牛血样中E2和P4浓度呈波动式变化。其中,E2分别在排卵后第13天d下降到基础水平。FSH在排卵后的第10天出现峰值;LH在排卵前2天出现峰值;INH在排卵后第4天出现峰值。各种激素之间存在相关性。FSH、LH和INH三者两两之间存在极显著相关性,INH与E2、P4存在显著相关性,E2与P4存在极显著相关性。[结论]该研究可为指导适时配种、提高广西本地沼泽型母水牛的繁殖力提供理论参考。     

Antibody domain exchange is an immunological solution to carbohydrate cluster recognition

Human antibody 2G12 neutralizes a broad range of human immunodeficiency virus type 1 (HIV-1) isolates by binding an unusually dense cluster of carbohydrate moieties on the "silent" face of the gp120 envelope glycoprotein. Crystal structures of Fab 2G12 and its complexes with the disaccharide Manalpha1-2Man and with the oligosaccharide Man9GlcNAc2 revealed that two Fabs assemble into an interlocked VH domain-swapped dimer. Further biochemical, biophysical, and mutagenesis data strongly support a Fab-dimerized antibody as the prevalent form that recognizes gp120. The extraordinary configuration of this antibody provides an extended surface, with newly described binding sites, for multivalent interaction with a conserved cluster of oligomannose type sugars on the surface of gp120. The unique interdigitation of Fab domains within an antibody uncovers a previously unappreciated mechanism for high-affinity recognition of carbohydrate or other repeating epitopes on cell or microbial surfaces.     

天津白和长白成年母猪在发情期间和妊娠早期的生殖激素变化规律

用放免法测定了天津白和长白各6头成年母猪从发情-2 d到妊娠30 d之间外周血清中促黄体素(LH)、促卵泡素(FSH)、雌二醇和孕酮浓度的动态变化。结果显示,整个试验期内天津白猪血清中平均LH,FSH与孕酮浓度均一直高于长白猪。其中,在妊娠早期的LH浓度、发情后的FSH浓度与其二次峰值、妊娠4,9,12,16 d的孕酮浓度及其最大峰值,天津白猪都显著高于长白猪(P<0.05)。血清雌二醇浓度,仅在发情-1 d时呈现出品种差异,天津白猪显著高于长白猪。结果表明,在发情前后与妊娠早期,成年天津白与长白母猪血清中4种生殖激素浓度的变化规律都基本相似,但在浓度值变化方面存在明显差异。     

早期断奶对巴音布鲁克羊母羊血清生长类及生殖激素浓度的影响

[目的]研究早期断奶对巴音布鲁克羊母羊血清生长类及生殖激素浓度的影响.[方法]选择胎次一致,产羔日期接近,所产羔羊初生重差异不显著的健康巴音布鲁克羊母羊15只,分别于40和60 d实施早期断奶.试验分为:试验组母羊(Ⅰ组:羔羊40日断奶、Ⅱ组:羔羊60日断奶)和对照组(即自然条件下哺乳母羊).测定指标包括:IGF-Ⅰ、INS、T3、T4、FSH、LH、E2.[结果]1.试验组母羊血清中IGF-Ⅰ、INS浓度均高于对照组,差异不显著(P＞0.05);试验Ⅱ组T3低于对照组,差异不显著(P＞0.05);试验组T4浓度均高于对照组,其中试验Ⅱ组显著高于对照组(P＜0.05).2.生殖激素:试验组母羊E2显著高于对照组(P＜0.05),试验组FSH、LH均高于对照组,差异不显著(P＞0.05);[结论]试验组母羊血清中T4、E2浓度显著高于对照组,表明早期断奶更利于母羊正常生理机能的维持,对卵巢周期恢复和生殖功能重建具有一定促进作用.     

理囊散治疗排卵延迟不孕奶牛血清微量元素与激素的相关性分析

[目的]探讨理囊散治疗排卵延迟不孕奶牛血液生殖激素和微量元素含量关系,分析其相关性与回归方程.[方法]采用ELISA法测定理囊散治疗排卵延迟不孕奶牛前后血清中促卵泡激素（FSH）、促黄体激素（LH）、孕激素（P）和雌二醇（E2）的浓度,采用原子吸收光谱法测定血清Cu、Fe、Mn和Zn含量,分析4种激素和4种微量元素间的相关关系与回归方程.[结果]P浓度与Cu、Mn、Zn含量呈正相关,而与Fe含量呈负相关.E2浓度与Cu、Fe、Zn含量呈正相关,而与Mn含量呈负相关.FSH浓度与Fe含量呈正相关,而与Cu、Mn、Zn含量呈负相关.LH浓度与Cu、Fe含量呈正相关,而与Mn、Zn含量呈负相关.[结论]排卵延迟不孕奶牛血清中微量元素含量对激素的分泌有影响.     

小梅山猪发情周期生殖激素变化的研究

以ESR基因BB型小梅山母猪、大白母猪为研究对象,测定发情周期血清生殖激素(雌二醇、雌三醇、孕酮、促卵泡素和促黄体素)浓度,探讨小梅山猪高产的内分泌机制。结果表明:小梅山猪雌二醇、孕酮浓度均显著(P<0.05)高于大白猪,大白猪雌三醇和促黄体素浓度显著(P<0.05)高于小梅山猪,而两品种猪促卵泡素则无显著差异。初步认为在诸多生殖激素动态相互作用中,雌激素和孕酮是决定小梅山母猪(ESR基因BB型)繁殖力的主效激素。     

超排绵羊血液激素水平与超排效果

研究超排绵羊血液激素水平的动态变化与排卵结果的关系,以预测超排效果。用放射免疫法测定血清中促卵泡素(FSH)、促黄体素(LH)、孕酮(P4)、雌二醇(E2)和促乳素(PRL)5种激素动态变化。结果,处理期间,超排无反应组羊血清中FSH水平显著低于超排有反应组和对照组(P<0.05);处理组雌激素水平呈不规则升降,超排无反应组于发情日高于超排有反应组和对照组;对照组,LH于发情日峰值为(4.04±2.98)mIU/ml;超排无反应供体羊血清中P4水平的变化与超排有反应组的变化趋势相反;PRL在试验组和对照组间未发现差异。可见,处理后绵羊血清中部分激素的变化可作为预测超排效果的依据。     

Osmotic adaptation by gram-negative bacteria: possible role for periplasmic oligosaccharides

The cyclic (1----2)-beta-D-glucans produced by species of Agrobacterium and Rhizobium resemble the membrane-derived oligosaccharides of Escherichia coli in their periplasmic localization, intermediate size, and (1----2)-beta-D-glucan backbones. The regulation of the biosynthesis of cyclic (1----2)-beta-D-glucan by Agrobacterium tumefaciens is now shown to parallel the osmotic regulation of membrane-derived oligosaccharide biosynthesis in Escherichia coli. This result suggests a general role for periplasmic oligosaccharides in the osmotic adaptation of Gram-negative bacteria as ecologically diverse as enteric and soil bacteria.