铕螯合剂DTTAEuNa标记流行性出血热单克隆抗体的实验研究

用Ｎ′（对异硫氰基苄基）二乙三胺Ｎ１,Ｎ２,Ｎ３四乙酸铕钠（ＤＴＴＡＥｕＮａ）作为螯合剂,标记不同蛋白浓度的流行性出血热单克隆抗体（ＥＨＦＭｃＡｂ）,经ＳｅｐｈａｋｅｘＧ５０凝胶柱分离标记的单抗分子,通过对层析液的紫外吸收峰处的蛋白光密度,时间分辨荧光强度以及免疫活性测定表明：二批Ｅｕ标记单抗的比活性分别为７８和１４７个Ｅｕ３＋／ＥＨＦＭｃＡｂ,标记回收率分别为４１％和４２％,标记物的免疫活性良好,可用于流行性出血热的抗原及抗体检测     

时间分辨免疫荧光分析测定人血清铁蛋白

用一种新型非放射性免疫分析——时间分辨荧光免疫分析法测定人血清铁蛋白含量。方法灵敏度达2ng/ml;测量范围5—1500ng/ml;批内、批间变异系数分别为7.1±0.8％和10.0±1.3％(x±SD);回收率为98.4±7.4％。测定值与RIA法测定值比较,相关性良好。     

C肽与胰岛素双标记时间分辨荧光免疫分析法的建立及初步临床应用

建立钐(Sm3+)标记检测C肽(C-peptide)及铕(Eu3+)标记检测胰岛素(insulin)的双标记时间分辨荧光免疫分析法(TRFIA),并初步尝试检测人血C肽以及胰岛素含量.将抗C肽单克隆抗体(Biodesign No.E54094M)与抗insulin单克隆抗体(BiodesignNo.E86306M)混合包被96孔板,然后用Sm3+标记抗C肽单克隆抗体(Medix No.9103),Eu3+标记抗insulin单克隆抗体(Biodesign No.E86802M),运用双抗体夹心一步法建立C肽/胰岛素双标记时间分辨免疫荧光分析法.结果显示:C肽分析灵敏度为0.2μg/L,线性范围为0.5～22μg/L,平均回收率达到99.6%,分析内和分析间变异系数分别为4.6%～6.0%和5.1%～7.6%.胰岛素分析灵敏度为0.8 mU/L,线性范围为3.6～180 mU/L,平均回收率为99.4%,分析内和分析间变异系数分别为3.7%～6.0%和5.1%～8.0%.C肽/胰岛素双标记检测试剂与PerkinElmer公司对应的单标记进口试剂盒分别同时测定血清样本200份,检测结果高度相关,具有较好的一致性,相关系数分别为0.98与0.99.总之,自建C肽/胰岛素双标记时间分辨荧光免疫分析方法的性能均可以达到临床检测要求,有望替代现有国内外较为昂贵的单标记试剂,可用于胰岛素分泌不足导致的糖尿病诊断及糖尿病的大规模普查筛选.     

IgG-Eu-IDPA对抗原IOV的时间分辨荧光免疫检测

镧系螯合物已经被广泛应用于高灵敏度的时间分辨荧光免疫分析.但是,使用紫外光激发镧系螯合物会对生物分子和细胞产生很大的损害.合成了能够被可见光(最大波长565nm)激发的IgG-Eu-IDPA,并测量了IgG-Eu-IDPA的光谱属性,如荧光寿命、在不同pH值和不同浓度环境下的荧光强度.在自制的时间分辨荧光仪上使用IgG-Eu-IDPA作为荧光探针,检测IOV抗原.数据显示,它的灵敏度远远高于传统的荧光仪.结果表明,IgG-Eu-IDPA能够在高灵敏度的原位和活体分析中作为一种新的、有潜力的荧光探针.     

荧光标记IgHV1抗原九肽及其分离纯化

目的 :建立IgHV₁抗原九肽荧光标记及分离纯化的方法。方法 :利用硫代磷酸化的原理以荧光试剂标记IgHV₁抗原九肽 ,用葡聚糖凝胶 (Sephadex)G 1 5层析柱及聚丙烯酰胺凝胶电泳(PAGE)对荧光标记的IgHV₁抗原九肽进行分离纯化并以毛细管电泳技术进行鉴定。结果 :用毛细管电泳技术对纯化后样品进行鉴定 ,其电泳图谱只出现单一峰。结论 :初步建立IgHV₁抗原九肽荧光标记及分离纯化的方法     

时间分辨荧光免疫分析技术研究现状及进展

时间分辨荧光免疫分析是一种新型的超微量的免疫标记分析方法,集酶标记免疫分析和放射免疫分析等优点于一身,且无放射性污染等.本文主要介绍了时间分辨荧光免疫分析的原理、优点,螯合剂的种类,以及各种分析技术及其应用现状和进展.     

C3和C4植物叶片对光氧化响应的日变化

田间生长的C3植物花生和C4植物玉米分别于晴天上午9：00、中午12：00、下午15：00取样。中午12：00花生叶片的Fv／Fm较早上9：见下降16％,出现了光抑制现象,玉米叶片的Fv／Fm则未下降。不同时间取样的花生和玉米叶片经甲基紫精（MV） 强光的人为光氧化处理,叶绿素和类胡萝卜素出现不同程度的氧化降解,中午12：00降解幅度最大,15时降幅最小。植物叶片的抗氧化能力与其SOD活性相关,而与PEPCase的活性没有明显的相关性。光氧化处理后,花生和玉米的叶绿素荧光参数FV／Fm、qp、pSII都下降,花生在12：00的降幅最小,玉米的降幅最大。光氧化引起花生的qN和热耗散系数（KD）上升,玉米则都下降．结果显示C3植物花生和C4植物玉米对光氧化的响应可能存在不同的机制。     

固相时间分辨荧光免疫螯合剂 BCPDA 的制备及其标记技术

报道了固相时间分辨荧光免疫螫合剂4,7-二氯磺基苯-1,10-菲罗啉-2,9-二羧酸(BCPDA)的制备方法,BCPDA 标记蛋白质及螫合 Eu³⁺方法,BCPDA-Eu³⁺标记物荧光光谱研究以及固相时间分辨荧光免疫分析法检测甲胎蛋白异质体(AFP-R-LCA)方法的建立.结果表明 BCPDA 能在温合条件下与蛋白质氨基结合并与 Eu³⁺螯合,BCPDA-Eu³⁺蛋白质标记物荧光特性、标记比度、生物结合活性与国外同类产品一致,所建立的检测 AFP-R-LCA 免疫分析法最小检测值0.6ng/ml,为提高我国非放射性同位素标记技术水平奠定了基础.     

碱性磷酸酶标记链霉亲和素

碱性磷酸酶标记链霉亲和素（AP-SA）是酶放大时间分辨荧光免疫分析（EATRFIA）通用的、最关键的试剂.报告了AP-SA的戊二醛二步标记方法.用自行研制的荧光发展溶液和AP的底物5-氟水杨酸磷酸酯测定了标记物AP-SA的特性,AP的标记回收率为38.7%;AP-SA稀释200～12 800倍时,稀释倍数和Tb的信/噪比呈线性关系;至少在两个月内,AP-SA的酶活性是稳定的.     

C3与C4植物的环境调控

环境条件决定着不同光合类型植物的地理分布范围和区域 ,一般来说 ,C4 植物分布于高温、强光的环境而 C3植物分布于阴凉、湿润的环境 ,且 C4 比 C3植物光合速率高。但环境条件影响着不同光合类型植物的光合潜能的发挥 ,C4 植物在高温、强光、干旱条件下所表现出来的优势在其它环境条件下未必就显现出来。环境条件甚至可以引起 C3、C4 光合途径间的相互转化 ,这使得目前几种鉴别植物光合类型的方法出现不一致的结果。因此 ,在判断植物的光合类型时 ,要注意多种手段的综合利用 ,同时注意植物所处环境条件的影响。     

现代荧光免疫分析技术应用及其新发展

免疫分析作为一类特殊的试剂分析技术,已经被广泛应用于多个不同领域。作为免疫分析方法家族中的一员,现代荧光免疫分析技术在相关领域里也扮演了重要角色。现代荧光免疫分析技术主要包括荧光偏振免疫分析(FPIA)和时间分辩荧光免疫分析(TRFIA)两种技术。本文从原理角度出发,综述了FPIA和TRFIA近年来在分析领域中的应用,并且阐述了二者的一些最新发展动态。     

Surface lipid composition of C3 and C4 plants

The characteristic surface lipid compositions of several C₃ and C₄ plants are discussed. C₄ plants produce surface lipids (epicuticular waxes) made up of the ubiquitous classes of aliphatic compounds: free fatty acids, aldehydes, primary alcohols, alkanes and aliphatic linear esters. C₃ plants synthesize surface lipids comprising the ubiquitous classes and either of the two following groups of compound: (i) lβ-diketones, hydroxy lβ-diketones, alkan-2-ol esters; (il) ketones and secondary alcohols with the functional group in the middle of the hydrocarbon chain. These features are suggested to represent physioIogical characteristics of the plant and to be related to ecological adaptations. Wax class compositions might also be an ancillary method for defining the C₃ or C₄ mechanism of CO₂ assimilation in cases where uncertainty exists.     

综述与专论: 河鲀毒素的检测技术与应用

河鲀毒素（tetrodotoxin, TTX）是毒性极强的小分子生物碱类毒素,包括中国在内的亚洲沿海国家因误食TTX污染食品而中毒的事件时有发生,其发病迅速且无特效解毒剂,对环境安全、食品安全与社会安全造成极大的威胁。通过检测食品与环境中的TTX含量可以实现TTX的风险预警,可有效防范TTX中毒事件的发生。本文梳理了4类TTX的检测技术,分析比较了传统的生物检测法、化学检测法、免疫检测法之间的优势、不足与实际应用进展,介绍了基于适配体技术的新型检测技术的兴起、发展与广阔的应用前景,对生物安全领域中TTX风险的管理与控制有现实意义。     

The fate of radiolabelled C28 and C29 phytosterols in the honey bee

The fate of radiolabelled campesterol, sitosterol and 24-methylenecholesterol fed in chemically-defined diets to honey bee (Apis mellifera L.) workers was determined. At various intervals, sterols of prepupae, newly emerged adults and queens were analyzed qualitatively, quantitatively and radiochemically and it was determined that there was not sufficient radioactivity associated with cholesterol and/or desmosterol in any of the samples to verify that any of the three C₂₈ and C₂₉ sterols was dealkylated and converted to cholesterol. Similarly, there was no evidence for the conversion of campesterol or sitosterol to 24-methylenecholesterol. It was concluded that the major portion of the sterols incorporated into the tissues of the brood larvae originated from the worker bees used to establish the colony. There is good evidence supporting the premise that the workers can make available sterols from their endogenous pools to the nutrient in the hive and that they can replenish these sterols with those from the artificial diet. The queen is also able to replenish sterols utilized in egg production from those obtained by the workers from the artificial diet, and at the end of nine weeks queens contained more than four times as much sterol, on a ‘μg sterol per g fresh weight’ basis, than was found in fertile queens at the beginning of the test period.     

Functional properties of diapophytoene and related desaturases of C30 and C40 carotenoid biosynthetic pathways

The desaturation reactions of C₃₀ carotenoids from diapophytoene to diaponeurosporene was investigated in vitro and by complementation in Escherichia coli. The expressed diapophytoene desaturase from Staphylococcus aureus inserts three double bonds in an FAD-dependent reaction. The enzyme is inhibited by diphenylamine. In the complementation experiment diapophytoene desaturase was able to convert C₄₀ phytoene to some extend but exhibited a high affinity to ζ-carotene. Comparison to the reaction of a phytoene desaturase from Rhodobacter capsulatus catalyzing a parallel three-step desaturation sequence with the corresponding C₄₀ carotenes revealed that this desaturase can also convert C₃₀ diapophytoene. Other homologous bacterial C₄₀ carotene desaturases could also utilize C₃₀ substrates, including one type of ζ-carotene desaturase which converted diaponeurosporene to diapolycopene. Further complementation experiments including the diapophytoene synthase gene from S. aureus revealed that the C₃₀ carotenogenic pathway is determined by this initial enzyme which is highly homologous to C₄₀ phytoene synthases.     

Photosynthetic traits in C3 and C4 grassland species in mesocosm and field environments

The North American tallgrass prairie is composed of a diverse mix of C₃ and C₄ plant species that are subject to multiple resource limitations. C₄ grasses dominate this ecosystem, purportedly due to greater photosynthetic capacity and resource-use efficiency associated with C₄ photosynthesis. We tested the hypothesis that intrinsic physiological differences between C₃ and C₄ species are consistent with C₄ grass dominance by comparing leaf gas exchange and chlorophyll fluorescence variables for seven C₄ and C₃ herbaceous species (legumes and non-legumes) in two different settings: experimental mesocosms and natural grassland sites. In the mesocosms, C₄ grasses had higher photosynthetic rates, water potentials and water-use efficiency than the C₃ species. These differences were absent in the field, where photosynthetic rates declined similarly among non-leguminous species. Thus, intrinsic photosynthetic advantages for C₄ species measured in resource-rich mesocosms could not explain the dominance of C₄ species in the field. Instead, C₄ dominance in this ecosystem may depend more on the ability of the grasses to grow rapidly when resources are plentiful and to tolerate multiple limitations when resources are scarce.     

Manipulation by 25-azacycloartanol of the relative percentage of C10, C9 and C8 side-chain sterols in suspension cultures of bramble cells

The addition of 25-azacycloartanol to the medium of suspension cultures of bramble cells resulted, after 6 weeks of growth, in a large decrease in the percentage of C₁₀ side-chain sterols, sitosterol and isofucosterol (83 % of the total in the control, 9 % in the treated cells), and in a spectacular increase in the percentage of C₈ side-chain sterols, cycloartenol, desmosterol and cholesterol (less than 1 % in the control, 53 % in the treated cells). In addition the relative percentage of C₉ side-chain sterols, mainly 24-methylene cholesterol increased significantly (from 16 to 37 %). A secondary effect of 25-azacycloartanol consisted in an increase of the percentage of Δ²⁴ sterols and in a decrease of the percentage of sterols with a saturated side chain. These results are in agreement with an inhibition by 25-azacycloartanol of the C-24 and C-28 methyltransferases and of the Δ²⁴ reductase.     

Metal complexes of virus inhibitors. Part III. Coordination properties of 1-n-propyl-2-α-hydroxybenzylbenzimidazole and the X-ray crystal structure of Ni(C17H18N2O)2(C17H17N2O)1(ClO4)1

Complexes are described of Cobalt(II) and Nickel- (II) salts with the title ligand L. The X-ray crystal structure is described of NiL₂L′₁(ClO₄)₁. One ligand molecule (L′) in this complex is deprotonated and the structure involves strongly hydrogen bonded dimers with OHO bonds = 2.56 Å and 2.62 Å and a NiNi bond = 4.77 Å. The corresponding Cobalt complex is thought to be similar but no other compounds containing L′ were obtained.     

Differential sensitivity of C3 and C4 turfgrass species to increasing atmospheric vapor pressure deficit

Temperature and vapor pressure deficit (VPD) effects on turfgrass growth are almost always confounded in experiments because VPD commonly is substantially increased in elevated-temperature treatments. The objective of this study as to examine specifically the influence of VPD on transpiration response of four ‘warm-season’ (C₄) and four ‘cool-season’ (C₃) turfgrasses to increasing VPD at a stable temperature (29.3 ± 1.5 °C). Although transpiration rates were noticeably lower in C₄ grasses, transpiration rates increased linearly in response to increasing VPD across the range of 0.8–3.0 kPa. In contrast, transpiration rates of C₃ increased sharply with increasing VPD across the range of low VPDs, but became constrained at higher VPDs (>1.35 kPa). Restricted transpiration rate at elevated VPD was most evident in Agrostis palustris and Lolium perenne. Assuming restricted transpiration rates reflect a limitation on leaf CO₂ uptake, these results indicate that the commonly observed decline in growth of C₃ (and success of C₄) grasses at elevated temperature may include a sensitivity to elevated VPD.