A NEW KIND OF ION-SELECTIVE ELECTRODE BASED ON CONDUCTING POLYMER FILM

Organic conducting polymers have attracted much interest in material science. This letter reports potentiometric response behavior of polypyrrole (PPy)polymer film electrodes prepared by electrochemical polymerization, and a new kind of ion selective

SYNTHESIS OF [LI.3DME] [(ETA-5-C5H5)3NDC6H5]

The phenyl derivatives of lanthanides Sc(C_6H_5)_3, Y(C_6H_5)_3, LiLa (C_6H_5)_4 and LiPr(C_6H_5)_4 were prepared by Hart et al. in 1970, and dis(cyclopentadienyl) phenyl complexes of lanthanides have been isolated recently. We reported here the synthesis and crystallography parameters of a new type of phenyl derivative of neodymium:

Identification and characterization of a myeloid differentiation factor 88 (MyD88) cDNA from Zhikong scallop Chlamys farreri

Myeloid differentiation factor 88 (MyD88) is a universal and essential adapter for the TLR/IL-1R family. In this report, the first mollusk Myd88 ortholog (named as CfMyd88) was cloned from Zhikong scallop (Chlamys farreri). The full-length cDNA of CfMyd88 was of 1554 bp, including a 5 '-terminal untranslated region (UTR) of 427 bp, a polyA tail, and an open reading frame (ORF) of 1104 bp encoding a polypeptide of 367 amino acids containing the typical TLR and IL-1R-related (TIR) domain and death domain (DD). Homology analysis revealed that the predicted amino acid sequence of CfMyd88 was homologous to a variety of previously identified Myd88s with more than 30% identity. The temporal expressions of CfMyd88 mRNA in the mixed primary cultured haemocytes stimulated by lipopolysaccharide (LPS) and peptidoglycans (PGN) were measured by real-time RT-PCR system. The mRNA expression of CfMyd88 decreased after stimulation with both LPS and PGN, and the lowest level was about 1/3 times (at 6 h) and 1/10 times (at 9 h) to that in the control group, respectively. The expression then recovered and was upregulated to two-fold at 9 h after LPS stimulation or to the original level at 12 It after PGN stimulation. The results suggest that the MyD88-dependent signaling pathway exists in scallop and was involved in the defense system. (c) 2007 Elsevier Ltd. All rights reserved.

Identification of archaeon-producing hyperthermophilic alpha-amylase and characterization of the alpha-amylase

The extremely thermophilic anaerobic archaeon strain, HJ21, was isolated from a deep-sea hydrothermal vent, could produce hyperthermophilic alpha-amylase, and later was identified as Thermococcus from morphological, biochemical, and physiological characteristics and the 16S ribosomal RNA gene sequence. The extracellular thermostable alpha-amylase produced by strain HJ21 exhibited maximal activity at pH 5.0. The enzyme was stable in a broad pH range from pH 5.0 to 9.0. The optimal temperature of alpha-amylase was observed at 95 degrees C. The half-life of the enzyme was 5 h at 90 degrees C. Over 40% and 30% of the enzyme activity remained after incubation at 100 degrees C for 2 and 3 h, respectively. The enzyme did not require Ca2+ for thermostability. This alpha-amylase gene was cloned, and its nucleotide sequence displayed an open reading frame of 1,374 bp, which encodes a protein of 457 amino acids. Analysis of the deduced amino acid sequence revealed that four homologous regions common in amylases were conserved in the HJ21 alpha-amylase. The molecular weight of the mature enzyme was calculated to be 51.4 kDa, which correlated well with the size of the purified enzyme as shown by the sodium dodecyl sulfate-polyacrylamide gel electrophoresis.

Cloning and recombinant expression of a crustin-like gene from Chinese shrimp, Fenneropenaeus chinensis

Antimicrobial peptides or proteins (AMPs) are proved to be one of the most important humoral factors to resist pathogen infection. As an antimicrobial protein, crustin had been described in invertebrates as a component of the innate immune system. A crustin-like gene (CruFc) was cloned from haemocytes of Chinese shrimp Fenneropenaeus chinensis by 3' and 5'-RACE PCR. The full-length cDNA consists of 523 with 405 bp open reading frame encoding 134 amino acids and the deduced peptide contains a putative signal peptide of 17 amino acids. The sequence also contains a whey-acidic protein (WAP) domain at the C-terminal. Transcripts of CruFc were mainly detected in haemocytes and gill by RT-PCR analysis. In addition, another full-length cDNA named CshFc was also cloned from haemocytes of Chinese shrimp and its inferred amino acid sequence lacks the WAP-type 'four-disulfide core' domain. The fusion proteins containing CruFc and CshFc were, respectively, produced and the antimicrobial assays revealed that the recombinant CruFc could inhibit the growth of grain-positive bacteria in vitro but the recombinant CshFc could not inhibit at the same conditions. The difference of antimicrobial activity between recombinant CruFc and CshFc provides the evidence that the four-disulfide core domain of crustin may play an important role in its biological function. (c) 2006 Elsevier B.V. All rights reserved.

Expression of Scophthalmus maximus CD83 correlates with bacterial infection and antigen stimulation

CD83 is a transmembrane glycoprotein of the immunoglobulin (Ig) superfamily and a surface marker for fully matured dendritic cells (DCs) in humans and mice. In teleosts, DC-like cells and their molecular markers are largely unknown. In this report, we described the identification and expressional analysis of a CD83 homologue, SmCD83, from turbot Scophthalmus maximus. The open reading frame of SmCD83 is 639 bp, which is preceded by a S'-untranslated region (UTR) of 87 bp and followed by a 3'-UTR of 1111 bp. The SmCD83 gene is 4716 bp in length, which contains five exons and four introns. The deduced amino acid sequence of SmCD83 shares 40-50% overall identities with the CD83 of several fish species. Like typical CD83, SmCD83 possesses an Ig-like extracellular domain, a transmembrane domain, and a cytoplasmic domain. The conserved disulfide bond-forming cysteine residues and the N-linked glycosylation sites that are preserved in CD83 are also found in SmCD83. Expressional analysis showed that constitutive expression of SmCD83 was high in gill, blood, spleen, muscle, and kidney and low in heart and liver. Bacterial infection and poly(I:C) treatment enhanced SmCD83 expression in kidney in time-dependent manners. Likewise, bacterial challenge caused significant induction of SmCD83 expression in cultured macrophages. Vaccination of turbot with a bacterin and a purified recombinant subunit vaccine-induced significant SmCD83 expression during the first week following vaccination. These results demonstrate that SmCD83 expression correlates with microbial challenge and antigen stimulation, which suggests the possibility that there may exist in turbot DC-like antigen-presenting cells that express SmCD83 upon activation by antigen uptake. In addition, these results also suggest that SmCD83 may serve as a marker for activated macrophages in turbot. (C) 2010 Elsevier Ltd. All rights reserved.

Isolation and characterization of the oxygen-evolving photosystem II complex from the economical red alga Bangia fusco-purpurea

The highly pure and active photosystem II (PSII) complex was isolated from Bangia fusco-purpurea (Dillw) Lyngb., an important economic red alga in China, through two steps of sucrose density gradient ultracentrifugation and characterized by the room absorption and fluorescence emission spectra, DCIP (2,6-dichloroindophenol) reduction, and oxygen evolution rates. The PSII complex from B. fusco-purpurea had the characteristic absorption peaks of chlorophyll (Chl) a (436 and 676 nm) and typical fluorescence emission peak at 685 nm (Ex = 436 nm). Moreover, the acquired PSII complex displayed high oxygen evolution (139 mu mol O-2/(mg Chl h) in the presence of 2.5 mM 2,6-dimethybenzoqinone as an artificial acceptor and was active in photoreduction of DCIP (2,6-dichloroindophenol) by DPC (1,5-diphenylcarbazide) at 163 U/(mg Chl a h). SDS-PAGE also suggested that the purified PSII complex contained four intrinsic proteins (D1, D2, CP43, and CP47) and four extrinsic proteins (33-kD protein, 20-kD protein, cyt c-550, and 14-kD protein).

海藻类胡萝卜素的化学分析及抗氧化活性研究

类胡萝卜素是分布最广泛，最重要的一类色素，海藻则是天然类胡萝卜素的主要资源库之一。本研究运用化学提取法并结合色层分析和光谱分析，对红绿褐三类海藻中代表性种类的类胡萝卜素总含量及各组分的定性定量进行了测定。发现绿藻类胡萝卜素含量相对最高，一般高出红藻和褐藻2～3倍，且种类最为丰富；褐藻类胡萝卜素含量相对略高于红藻，有其自己的特征色素-褐藻黄素，且是含蓄量最丰富的一种天然海藻类胡萝卜素。其中，红藻中玉米黄素和三色堇黄素含量较高，绿藻中玉米黄素和叶黄素含量较高，褐藻中褐藻黄素和三色堇黄素含量较高。鉴于绿藻中松藻类胡萝卜素的含量相当高，种类也很丰富，可以作为首选的资源种。以邻苯三酚的自氧化体系作为超氧阴离子自由基O_2的产生体系，对海藻中主要的类胡萝卜素在离体条件下清除该种自由基的能力进行了测定。本研究主要集中于对大量物种进行抗氧化活性的筛选，其中三色堇黄素单独清除自由基的能力最强，其清除率可达成12%左右；β-胡萝卜素、玉米黄素和褐藻黄素与维生素E的抗击氧化协同作用较强，比各自的自由基清除能力增强约80%。通过对含量分布和抗击氧化活性进行比较，以期筛选到较有利用价值的海藻种类作为实验材料进行后续的类胡萝卜素生理和药理活性实验。

潮间带纤毛虫原生动物和小型底栖动物生态学研究

微型和小型底栖动物是底栖微/小食物网的重要构成。相对浮游生态系统, 迄今国际间对底栖食物网的认知极为欠缺。这一方面是由于微型生物形态和功能上的复杂性和多样性, 另一方面原因在于研究方法的障碍—主要是微型和小型底栖动物的定量提取和定性分析。本研究首先进行了方法学改良, 并应用新方法对底栖微食物网的重要功能类群—纤毛虫原生动物和小型底栖动物进行了不同生境的周年按月采样, 定性及定量研究的同时, 联系环境因子对微型和小型底栖生物的环境监测进行了探讨。 微型和小型底栖生物的定量研究首先涉及到目标生物在沉积物中的有效提取, 目前硅胶液提取是普遍使用的方法, 其中Ludox液主要应用于小型生物, 它不但价格便宜而且比重合适, 因此在常规生态研究中被广为接受。不过, Ludox易与于海水中的阳离子产生凝结而无法直接用于微型生物; 目前唯一直接应用于微型生物提取的是Percoll硅胶液, 但其昂贵的价格使其在常规生态研究中受到极大限制。本研究以价格低廉的Ludox 硅胶液结合定量蛋白银染色 (QPS) 技术开发了一种新的方法, 即Ludox-QPS法。主要流程为: 样品采集与固定、淘洗/稀释降盐、Ludox密度梯度离心、过滤浓缩和琼脂包埋, QPS染色、永久封片及鉴定计数。添加已知数量的纤毛虫至无生物底泥的重获实验表明, 该密度梯度离心的提取率大于94%; 该方法对自然沉积物中纤毛虫的提取率达97.6%, 对沙质、泥沙质和泥质中海洋线虫的提取率分别达97%、96.9% 和97.8%。对比实验表明, 经QPS制片获得的小型动物的丰度和类群数量与传统方法相当或更高, 尤其当小个体虫体占优势时, 该法显示出较传统方法 (导致数量低估) 更为明显的定量优越性。该方法除用于纤毛虫和小型动物的定量分析外, 还具有较高的分类分辨率, 染色后的纤毛虫原生动物大多类群可鉴定到属, 部分可鉴定到种, 以此可在群落水平上研究其生态作用。 根据新开发的Ludox-QPS技术, 在大沽河潮间带依据盐度梯度选定2个站位 (IIQ和营海) 进行了周年按月采样, 对底栖纤毛虫和小型底栖动物进行了定量研究。纤毛虫原生动物在IIQ和营海的年平均丰度分别为2236 inds./10 cm2 和935 inds./10 cm2 (28 inds./ml 和12 inds./ml), 平均生物量分别为119.1 gC/10 cm2和54.2 gC/10 cm2 (1.5 gC /ml 0.7 gC/ml)。丰度的季节变化趋势为: 春天 > 秋天 > 夏天 > 冬天。垂直分布上, 在营海分布于表层0-0.5 cm 的比例为57.1%, 分布于0.5-2 cm、2-4 cm和4-8 cm比例分别为23.1%、11.4% 和8.5%; 13个月中除12月份外, 4-8 cm均有一定数量的纤毛虫分布; 而在IIQ, 97% 的纤毛虫分布在0-0.5 cm, 分布在0.5-2 cm、2-4 cm和4-8 cm比例分别为2.4%、0.4%和0.2%, 4-8 cm的分布只发生在春季和秋季。纤毛虫的多样性季节变化明显, 春秋季物种丰富, 两个站点每毫升沉积物的平均物种数分别为18和6。Two-Way Crossed ANOSIM 分析表明纤毛虫群落在月份间和站点间的差异极其显著。Pseudochilodonopsis sp., Chilodontopsis sp., Euplotes sp.及Prorodon sp.是表征两个生镜中纤毛虫群落的主要类群。 同时, 发现了14个小型生物类群, 其中线虫在IIQ和营海的丰度优势度分别为97.4% 和78.6%。小型动物在IIQ和营海的年平均丰度分别为4793 inds./10 cm2和8915 inds./10 cm2 (60 inds./ml和111 inds./ml), 其生物量分别为1068.8 gC /10 cm2和1790 gC /10 cm2 (13.4 gC/ml和22.4 gC/ml)。小型底栖动物的丰度在IIQ的季节变化为: 夏季 (7888 inds./10cm2) > 秋季 (5447 inds./10cm2) > 春季 (3731 inds./10cm2) > 冬季 (2780 inds./10cm2); 在营海则完全相反: 冬季 (15579 inds./10cm2) > 春季 (10691 inds./10cm2) > 秋季 (6611 inds./10cm2) > 夏季 (4667 inds./10cm2)。小型底栖动物和纤毛虫的相对重要性存在明显的区域和季节差异。 纤毛虫原生动物、小型动物及环境因子的相关分析表明, 纤毛虫的丰度和多样性与温度和盐度及有机质含量显著相关, 与小型动物没有显著相关性; 群落结构分析表明, 温度、有机质和小型动物的丰度的组合与纤毛虫群落丰度的相关系数为0.345; 盐度、脱镁叶绿素、有机质和小型动物生物量的组合与纤毛虫群落多样性的相关系数为0.403。依据海洋线虫和桡足类的比值 (N/C) 推测, IIQ 可能存在严重的有机污染, 营海则存在明显的季节波动, 8月和9月及2月可能是污染最严重的季节, 这种状况在纤毛虫群落结构的CLUSTER聚类中得到验证。虽然目前尚没有形成有关微型底栖生物-纤毛虫原生动物的污染检测的直接依据, 但本研究说明纤毛虫群落的确对环境污染具有一定的感应度, 而且这种感应和利用小型生物的主要类群估算的污染检测 (N/C) 存在一定程度的关联。 90年代早期有关青岛湾有机污染带的研究表明, 经彻底截污后, 其环境状况向良性发展。进一步了解该湾的健康状况, 2006.5-2007.5月对该湾沙质和泥沙质的小型动物进行周年按月采样。小型动物在泥沙质和砂质沉积物中的年平均丰度分别为4853 ± 1292 inds./10 cm2和1528 ± 569 inds./10 cm2; 年平均总生物量分别为1434.1 ± 897.0 gC /10cm2和720.7 ± 353.8 gC/10cm2。沙质底小型生物的丰度季节波动明显, 6月份和12月份最高, 3月份和9月份最低; 泥沙质季节波动不明显, 6月份最高。两个站点均有48%的小型动物分布在0-0.5 cm 表层, 海洋线虫在表层的分布比例分别为48% (泥沙质) 和34% (砂质)。共检获14个小型动物类群, 其中线虫在泥沙质和砂质沉积物中的年平均丰度分别4619 ± 1255 inds./10cm2和1014 ± 376 inds./10cm2, 其丰度优势度分别为95.2%和66.4%。其它在丰度上占优势的类群, 泥沙质依次为多毛类 (1.5%)、甲壳幼体 (1.5%) 和桡足类 (0.7%); 沙质依次为: 甲壳类幼体 (12.6%)、腹毛类 (8.3%) 和 桡足类 (6.2%)。CLUSTER聚类分析表明, 泥沙质和和砂质中小型生物的丰度组成具有64%的相似性。BIOENV分析表明, 温度、盐度、中值粒径和粘土粉砂含量的组合最能解释不同月份之间和不同站位间的差异, 其相关系数为0.614。依据小型生物的丰度和类群组成, 表明泥沙质底尚存一定的有机污染。

Chemical Constituents of Nitraira tangutorum Seed from Qaidam Basin

Six compounds were isolated from the 75% ethanol extract of Nitraria tangutorum seed.On the basis of spectroscopic methods including 1H NMR,13C NMR and ESI-MS and comparison with literature,their structures were elucidated as daucosterol(1),4-hydroxypipecolic acid(2),quercetin(3),allantoin(4),1,2,3,4-tetrahydro-1-methyl-β-carboline-3-carboxylic acid(5) and L-tyrosine(6).Compounds 1,2,3,5 and 6 were isolated from Nitraria tangtorum for the first time.

珠芽蓼果实营养成分分析

本文对珠芽蓼果实的营养成分进行了分析.结果表明,珠芽蓼果实含有丰富的蛋白质、总糖、氨基酸和矿质元素,是一种值得有效开发的野生植物资源.

Diterpenoids from Euphorbia wallichii

Object To study the chemical constituents of Euphorbia wallichii.Methods The constituents were repeatedly separated and purified on silica gel column.They were identified on the basis of spectral methods.Results Nine diterpenoids were obtained from the roots of E. wallichii.Among them jolkinol B(I) is lathyrane type;caudicifolin (Ⅱ),helioscopinolides A(Ⅲ),C(Ⅳ),and E(Ⅴ) belong to abietane type;while ent-atisane-3β,16α,17-triol(Ⅵ),ent-16α,17-dihydroxyatisan-3-one(Ⅶ),ent-3β,(13S)-dihydroxyatis-16-en-14-one(Ⅷ),and ent-2-hydroxy-atis-1,16(17)-dien-3,14-dione(Ⅸ) possess an ent-atisane skeleon.Conclusion All of them are isolated from E. wallichii for the first time.

赤狐气味对高原鼠兔繁殖的影响

在野外条件下，利用赤狐的粪尿气味增加高原鼠兔的捕食风险，研究捕食风险对高原鼠兔繁殖的影响。结果表明，作为衡量高原鼠兔繁殖投入大小的定量指标，成体高原鼠兔的体重变化在捕食风险处理样方与对照样方之间没有明显的不同，随着繁殖期的延长，两样方内雌雄个体的体重均显著减少，说明捕食风险对高原鼠兔的繁殖投入无明显影响，因此，捕食风险对幼体的生长、发育也无明显的作用。捕食风险增加后，高原鼠兔平均每个雌性成体拥有的后代数目、性比和居留率与对照样方比较均无明显不同，但是由于扩散等原因使每个雄性成体拥有的后代数、繁殖期结束后幼体的性比有明显的差异。以上结果并未显示出捕食者气味作为捕食风险对高原鼠兔的繁殖产生抑制作用，其主要原因是捕食风险的类型不同和研究期间高原鼠兔本身承受的捕食风险较大，高原鼠兔可能通过行为变化调节捕食风险增加对其产生的不利影响。

款冬的胚胎学

系统报道了中藏药款冬大小孢子的发生、雌雄配子体发育和胚胎的发育过程。药壁发育双子叶型; 绒毡层发育接近菊科中的“The Com os bip innatus”型; 成熟花粉为3 细胞型; 单珠被, 薄珠心, 倒生胚珠；具发达的珠被绒毡层；胚囊发育4 孢子型, 接近五福花(A d ox a)型胚囊。受精作用属于有丝分裂前配子体融合类型。胚乳发育为核型。胚胎发育为紫菀型千里光变型。讨论了该种胚胎学特征的生态学及系统学意义。