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MEP is a member of thioester-containing protein (TEP) family found in Zhikong scallop Chlamys farreri and is involved in innate immunity against invading microbes. In the present study, the genomic DNA of CfTEP was cloned and characterized. The genomic DNA sequence of CfTEP consisted of 40 exons and 39 introns spanning 35 kb with all exon-intron junction sequences agreeing with the GT/AG consensus. The genomic organization of CfTEP was similar to human and mouse 0 rather than ciona C3-1 and Drosophila dTEP2. By RT-PCR technique, seven different cDNA variants of CfTEP (designated as CfTEP-A-CfTEP-G) were cloned from scallop gonad. CfTEP-A-CfTEP-F were produced by alternative splicing of six mutually exclusive exons (exons 19-24), respectively, which encoded the highly variable central region. While in CfTEP-G, the deletion of all the six exons introduced a new translation stop site and might trigger nonsense mediated decay (NMD). The mRNA expression and the proportion of the seven CfTEP variant transcripts were examined in the gonad of scallops after bacterial challenge. The fragments containing the highly variable central region of UTEP were amplified by RT-PCR and a 100 positive clones were sequenced randomly. The expression profiles of the seven MEP variants were different and displayed the sex and bacteria dependent manner. In the blank, sea water and Listonella anguillarum challenged subgroups of male scallops, all the transcripts detected were CfTEP-G isoform. In the Micrococcus luteus challenged subgroup, the isoforms expressed and their proportions were CfTEP-F (54%), CfTEP-B (23%), CfTEP-A (10%), CfTEP-C (7%) and CfTEP-E (6%). However, in the gonad of female scallops, only CfTEP-A were found in blank and sea water challenged subgroups. After L anguillarum or M. luteus challenge, four and five isoforms were detected, respectively, with CfTEP-F isoform being the most one in the both subgroups. These results suggested that the evolution of TEP genes was very complex, and that the diverse CfTEP transcripts generated by alternative splicing played an important role as pattern recognition receptors in the innate immune defense of scallops. (C) 2009 Elsevier Ltd. All rights reserved.

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中华绒螯蟹是我国重要的水产经济动物,近年来养殖规模不断扩大,产量持续增加。但是,伴随着养殖规模的扩大,养殖环境也日益恶化并导致了大量疾病的发生,严重制约了中华绒螯蟹养殖业的健康发展。因此,疾病预防和控制对中华绒螯蟹养殖业的可持续发展具有举足轻重的作用。与其他无脊椎动物一样,中华绒螯蟹的免疫系统没有免疫球蛋白和淋巴细胞,而是依靠由细胞免疫和体液免疫构成的固有免疫系统来对病原进行识别和清除。中华绒螯蟹的固有免疫机制的研究有助于推动中华绒螯蟹病害防治工作的开展。 本研究采用大规模EST测序方法,结合末端快速扩增(rapid amplification of cDNA ends,RACE)技术从中华绒螯蟹血淋巴中克隆到了过氧化物还原酶(peroxiredoxin,EsPrx6)和硫氧还蛋白(thioredoxin,EsTrx1)基因的cDNA 全长序列;采用实时荧光定量PCR 技术检测了这两个基因在健康个体中表达的组织分布情况以及鳗弧菌刺激后血淋巴细胞中的时序表达规律;同时,将这两个基因的编码区克隆到pET 系列载体,并在大肠杆菌中实现了重组表达,并进行了体外活性检测。 过氧化物还原酶是一个抗氧化蛋白超家族,在保护机体免受活性氧(reactive oxygen species,ROS)的伤害中发挥着重要作用。中华绒螯蟹Prx6(EsPrx6) 基因的cDNA 全长为1076 bp,5` UTR(untranslated region,UTR) 为69 bp,3` UTR 为347 bp,开放阅读框(open reading frame,ORF)为660 bp,编码219 个氨基酸的蛋白。mRNA 3`-端具有多聚腺苷酸加尾信号(polyadenylation signal)AATAAA 和polyA 尾巴。EsPrx6 的预测分子量为 24 kDa,理论等电点为6.21,具有一个保守的Prx 结构域、一个AhpC 结构域和过氧化物酶催化活性中心PVCTTE,表明EsPrx6 属于1-Cys 型Prx。在所检测的组织中均有EsPrx6 的表达,其中以肝胰腺表达量最高,为血淋巴细胞中表达量的17.4 倍。鳗弧菌刺激后,血淋巴细胞中EsPrx6 的表达下降,到12 h 时,实验组显著低于对照组(P<0.05);随时间推移,表达水平逐渐回升,但在整个实验期间,都没有恢复到起始水平。将EsPrx6 进行体外重组并在大肠杆菌E. coli BL21(DE3)中实现表达,重组EsPrx6 具有预期的抗氧化活性和过氧化物酶活性,其中抗氧化活力为14.69 U/mg 蛋白,高于相同条件下GSH 的抗氧化力(P<0.05),过氧化物酶活力为23.46 U/mg 蛋白。结果表明,EsPrx6 作为一种重要的抗氧化剂,在中华绒螯蟹抵御ROS 可能引起的氧化损伤方面具有重要作用。 硫氧还蛋白是广泛存在于生物体内的一种具有硫醇依赖性的具有还原活性的蛋白。中华绒螯蟹Trx1(EsTrx1)基因的cDNA 全长为641 bp,5` UTR 为17 bp,3` UTR 为306 bp,开放阅读框为318 bp,编码105 个氨基酸。EsTrx1 的预测分子量为12.2 kDa,理论等电点为4.8。EsTrx1 不含信号肽,其氨基酸序列与其他动物的Trx1s 具有高度相似性,如与地中海黄蝎的Trx1 相似度达到73%;而与其他物种Trx2 的同源性很低,相似度仅为14.3-22.8%,表明EsTrx1 属于Trx1 亚族。实时荧光定量PCR 检测发现,EsTrx1 在鳃、性腺、肝胰腺、肌肉、心脏和血淋巴细胞中都有表达。血淋巴细胞中EsTrx1 mRNA 的表达量在菌刺激后上升,刺激后6 h,实验组表达量显著高于对照组和空白组(P<0.05),然后逐渐恢复到刺激前水平。为进一步探讨其生物学功能,将EsTrx1 进行体外重组并在大肠杆菌E. coli BL21(DE3)得到表达,重组EsTrx1 具有预期的氧化还原调节活性,抗氧化活力为3.06 U/mg,且抗氧化活力高于GSH(P<0.05)。rEsTrx1 的二硫键还原活力为5.03,低于凡纳滨对虾的二硫键还原活力(10.44),接近于大肠杆菌(4.93),小牛胸腺(6.50)和小牛肝脏(5.09),而高于鲍鱼Trx2(1.83)活力。结果表明,EsTrx1 在生理条件下能够作为一种重要的抗氧化剂,参与对细菌感染的免疫应答反应。

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本文在区域背景分析的基础上,详细研究了中太平洋CP区(7°-12°N,176°E-178°W)和东太平洋CC区(7°-14°N,138°-152°W)铁锰结核的铁锰矿物组成、化学成分、成矿介质特征及其形成控制因素,结果表明:铁锰结核内部构造具有几乎由纯的铁锰氧化物组成的平行纹层状构造到含有较多碎屑矿物粘土矿物的斑杂状构造的连续过渡特征;铁锰结核中的锰矿物主要是δ-MnO_2、钡锰锰矿和钠水锰矿,且以前两者为主,在以平行纹层状构造为主的结核中富δ-MnO_2、贫钡镁锰锰,δ-MnO_2/钡镁锰矿比值大于10,而在以斑杂状构造为主的结核中δ-MnO_2/钡镁锰矿的比值在1左右,铁矿物主要是针铁矿、四方纤铁矿等;铁锰结核中的化学元素可以分成五个具有独立成因意义的组合:锰元素组、铁元素组、造岩元素组、生物成因元素组和易溶盐类组分,具平行纹层状构造富含δ-MnO_2的结核中富集铁组元素,具斑杂状构造富含钡锰锰矿的结核富集锰组元素和造岩元素;铁锰结核中稀土元素含量是正常深海沉积物的2-3倍。水成型结核和混合成岩型结核上部稀土元素更富且具Ce的明显正异常,而成岩型结核和混合成因结核的下部稀土元素含量相对低,Ce的正异常也不明显,有时出现负异常;铁锰结核的直接成矿介质是大洋底层水和孔隙水,因此底层水和孔隙的物理化学条件就是决定结核地球化学特征的关键条件,影响大洋底层水、孔隙水物理化学条件变化的地质因素主要有南极底流、沉积速率、生物生产力等等;铁锰结核的生长是一非线性振荡式的地质地球化学作用过程。

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能量代谢指动物在进行生理活动(如摄食、消化以及动物的活动等)时所消耗能量的总和,一般以动物的呼吸率利排泄率来估计动物的能量代谢。其主要研究内容是闸明生物能量代谢的基木规律以及与环境闪子的关系。菲律宾蛤仔(Ruditapesphil ippmarum)是我国一种重要的养殖贝类,关于其能量代谢的研究却较少,这种状况妨碍了菲律宾蛤仔养殖生态理论的完善和养殖技术的提高。本研究主要对菲律宾蛤仔呼吸率和排泄率的基本规律(能量代谢与体重的关系、能量代谢的昼夜变化)及其与环境因子(饵料浓度、水温、栖息底质环境)的关系进行探讨。研究结果如下:1.不同体重菲律宾蛤仔代谢率小同。实验川菲律宾蛤仔分三种大小:l(干肉重为0.07-0.14g)、ll(干肉重0.27-0.34g)、III(干肉重0.45~0.63g)。温度包括:26℃(八月)、20℃(十月)、1 5℃(十二月)、9℃(一月)。实验共设四个饵料浓度:2.28±0.25,6.454±0.44,10.284±0.82,15.414±1.56mgTPM/L(TPM,总颗粒物),饵料中POM(颗粒有机物)含量都为4.68±1.64 mg/L。常温下菲律宾蛤仔代谢率随着体重的增大而增大。15℃、20~C、26℃时蛤仔呼吸率与干肉重呈明显的幂函数关系R=aW~b,a值变动范围为0.1076-0.3309;b值变动范围为0.239l~0.8381;蛤仔排泄率与干肉重也呈明显的幂函数关系N=aW~b,a值变动范围为14.213~68.362:b值变动范围为0.3673-1.1 532。9℃(饵料浓度为2.28±0.25mgTPM/L)、20℃(饵料浓度为10.284-0.82mgTPM/L)、26℃(饵料浓度为6.454±0.44mgTPM/L)时不同体重蛤仔氧氮比差异显著,其它情况下不同体重蛤仔氧氮比差异不显著。2.常温下菲律宾蛤仔代谢率受饵料浓度的影响,不同大小蛤仔受饵料浓度的影响程度不同。I组蛤仔呼吸率受饵料浓度的显著影响,II组III组蛤仔呼吸率只在9℃(一月)和26~C(八月)时受饵料浓度的显著影响。26℃时影响最显著,26℃时I组蛤仔在饵料浓度为2.28±0.25,6.45±0.44,l0.28±0.82,15.4l±1.56mgTPM/L时呼吸率分别是O.086,0.146,0.073,0.093(mlO_2/h);ll组蛤仔在上述浓度饵料中呼吸率分别是0.138,0.214,0.J 26,0.12l(mlO_2/h);III组蛤仔在上述浓度饵料中呼吸率分别是0.129,0.266,0.186,0.192(mlO_2/h)。菲律宾蛤仔呼吸率在饵料浓度为6.45±0.44 mgTPM/L时最高,蛤仔呼吸率在其它饵料浓度时都会降低。菲律宾蛤仔排泄率在饵料浓度为10.28±0.82 mgTPM/L和15.4l士1.56mgTPM/L时显著高于其它浓度组,9℃时这种趋势更明显,9℃时饵料浓度为2.28±0.25,6.454±044,lO.284±0.82,15.41±1.56mgTPM/L中I组蛤仔排泄率分别是4.297,2.874,8.003,6.658(μgNH_3-N/h);II组蛤仔在上述浓度饵料中排泄率分别是4.011,3.609,10.427,12.732(μgNH_3-N/h);III组蛤仔在上述浓度饵料中排泄率分别是2.28 l,6.452,10.283,15.417(μgNH_3-N/h)。3.菲律宾蛤仔代谢率受自然温度的显著影Ⅱ向。I组蛤仔在9℃、15℃、20℃、26℃时呼吸率平均为0.057,0.085,0.039,O.099;II组蛤仔在上述四个温度中呼吸率平均为0.08,O.128,0.089,0.149(mlO_2/h),I组和II组蛤仔在9℃和20~C时呼吸率较低,在26℃时呼吸率最高。III组蛤仔在上述四个温度中呼吸率平均为0.09,O.1 59,O.143,O.193(mlO_2/h),在9℃时llI组蛤仔呼吸率显著低于其它温度组。温度为9℃、15℃、20℃、26℃时l组蛤仔排泄率平均为5.458,13.169,4.946,11.138(μgNH_3-N/h):II组蛤仔在上述温度中排泄率平均为7.695,23.578,8.319,23.90l(μgNH_3-N/h);III组蛤仔在上述温度中排泄率平均为11.738,27.443,15.658,35.407(μgNH_3-N/h),蛤仔排泄率在15℃和26℃时均高于9℃和20℃。4.摄食状态与饥饿状态菲律宾蛤仔代谢率有明显不同。26℃时蛤仔静止状态呼吸率平均为0.336(m102/g干重.h),摄食状态呼吸率平均为0.656(ml0_2干重.h),摄食状态呼吸率比静止状态平均升高了0 32(ml0_2/g干重.h);26℃时蛤仔静止状态排泄率平均为39.471(μgNH_3-N/g干重.h),摄食状态排泄率平均为88.08(μgNH_3-N/g干重.h),摄食状态排泄率比静止状态排泄率平均升高了48.6(μgNH_3-N/g干重.h)。摄食状态代谢率平均是静止状态的2~3倍。根据摄食引起的呼吸率和排泄率升高量得出每氧化产生lμgNH_3-N需0_2量平均为7.05μl。5.人工控制温度对菲律宾蛤仔代谢率有明显影响。不同大小蛤仔受温度的影响程度不同。在温度5℃、10℃、l 5℃、20℃、26℃,I组和II组蛤仔呼吸率都随着温度的升高而升高,在10℃~l5℃和20℃~26℃这二个温度变化范围内呼吸率变化最大,在20℃~26℃时I组蛤仔呼吸率变动范围为O.85~1.04(m10_2/g干重.h)、II组蛤仔变动范围为0.57~0.86(ml0_2/g干重.h)。III组蛤仔呼吸率只在5℃~l0℃时明显增高,变动范围为0.09~0.5l(m10_2/g干重.h),在10℃~26℃范围内变化不大。I组和II组蛤仔排泄率随着温度的升高而升高,变动幅度较大,在5℃~26℃范围内其排泄率变动范围为10.32~81.53(μgNH_3-N/g干重.h);而 III组蛤仔排泄率只在5℃~15℃时随着温度的升高而升高,其排泄率变动范围为6.75~23.77(μgNH_3-N/g干重.h),在15℃~26℃范围内几乎不变。III组蛤仔的适温范围比I组和II组蛤仔广。菲律宾蛤仔在5℃和10℃时氧氮比变化明显,变动范围为2.76~11.44,在15~26℃时变化不大。6.菲律宾蛤仔代谢率有明显的日节律性,呈正弦曲线型变化。蛤仔夜问代谢率明显升高。I组蛤仔夜间呼吸率平均为0.867(m10_2/g干重.h),白天呼吸率平均为O.504(m10_2/g干重.h);II组蛤仔夜间呼吸率平均为0.438(m10_2/g干重.h),白天呼吸率平均为0.36l(m102/g干重.h);III组蛤仔夜间呼吸率平均为0.409(m10_2/g干重.h),白天呼吸率平均为0.252(m102/g干重.h)。在22:00-23:00菲律宾蛤仔呼吸率最高。7.底质环境对菲律宾蛤仔的代谢率有明显影响。在饥饿状态下菲律宾蛤仔在泥沙底质中呼吸率平均为l 406(m10_2/g干重h),在无泥沙环境中呼吸率平均为O.963(ml0_2/g干重.h);摄食状态下菲律宾蛤仔在泥沙底质中呼吸率平均为1.59l(m102/g干重.h),在无泥沙环境中呼吸率平均为1.115(m10_2/g干重.h)。在饥饿状态下菲律宾蛤仔在泥沙底质中排泄率平均为78.934(μgNH_3-N/g 干重.h),在无泥沙环境巾排泄率平均为45.043(μgNH_3-N/g干重.h);摄食状态下菲律宾蛤仔在泥沙底质中排泄率平均为87.12l(μgNH_3-N/g干重.h),在无泥沙底质中排泄率平均为58.354(μgNH_3-N/g干重.h)。蛤仔在泥沙环境中呼吸率和排泄率都明显升高。

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利用新型荧光试剂2-(11H-苯[a]咔唑)乙基氯甲酸酯(BCEC-Cl)作为柱前衍生化试剂,在HypersilBDS C_(18)(200mm×4.6mm,5μm)反相色谱柱上,采用梯度洗脱对20种氨基酸衍生物进行了分离检测。在乙腈与Na_2B_4O_7缓冲液中,室温下BCEC-Cl与氨基酸反应5min可实现完全衍生。检测的激发和发射波长分别为λ_(ex)=279nm,λ_(em)=380nm。采用柱后质谱电喷雾离子源(ESI source)正离子模式,实现了水解牛血清白蛋白中氨基酸和油菜蜂花粉中氨基酸的定性定量检测。荧光定性检测的线性回归系数均大于0.9990,检出限为1.49~19.74fmol(S/N=3)。

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On a reversed phase Hypersil BDS C-18 (200 mm x 4. 6 mm, 5 mu m) column, 20 amino acids, which were derivatized using 2-(11H-benzo [a] carbazol-11-yl) ethyl carbonochloridate (BCEC-Cl) as pre-column derivatization reagent, were separated in conjunction with a gradient elution. Optimum derivatization was obtained by reacting of amino acids with BCEC-Cl at room temperature for 5 min in the presence of sodium borate catalyst in acetonitrile solvent. The fluorescence excitation and emission wavelengths were 279 nm and 380 nm respectively. The identification of amino acid derivatives from hydrolyzed bovine serum albumin and bee pollen was carried out by post-column mass spectrometry with electrospray ion source in positive ion mode. Linear correlation coefficients of the amino acid derivatives were > 0.9990, and detection limits (at signal to noise of 3:1) were 1.49 - 19.74 fmol for the labeled amino acids.

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The Xiao-wan Power Station is the second highest arch dam in the world under construction. The height of the dam is about 292m. Large-scale excavation in the dam foundation of Xiao-wan Power Station has brought intensive unloading phenomenon. We collected a large number of firsthand data on unloaded rock mass in dam foundation, which supplies a natural testing ground for researching unloaded rock mass after excavation. Detailed study was carried out on the parameters of unloaded rock mass in the dam foundation of Xiao-wan Power Station. The study is not only importance for the Xiao-wan Power Station, but also has important instruction significance to similar projects in the Southwest of China. In order to study the mechanical parameters of unloaded rock mass, large field and laboratory tests were carried out. The test results showed the size effect of the sample is obvious. The change of deformation modulus of rock is not obvious. However, the Poisson's ratio of rock is increased under unloaded condition, its value is even more than 0.5. The theoretical forecasted results is accordance to the field tests including sound wave data and deformation monitoring data, which shows the forecasted results were reasonable. The soften yield criterion was adopted in the thesis to study the characteristics of the brittle rock mass in order to simulate their brittle failures. Based on the study results above, the transform of the structural plane network model to the numerical one was carried out, which made it feasible to consider the influence of large amount joints on the mechanical characteristic of rock mass in the numerical analyses. Using a factor, the degree of the damage or strengthen of rock mass can be determined rapidly, which proposed a rapid and feasible method for the determination of the parameters of rock mass.

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Biofingerprinting chromatogram, analysis, which is defined as the comparison of fingerprinting chromatograms of the extract of traditional Chinese medicines (TCMs) before and after the interaction with biological systems (DNA, protein. cell. etc.), was proposed for screening and analysis of the multiple bioactive compounds in TCMs. A method of microdialysis sampling combined with high performance liquid chromatography (HPLC) was applied to the study of DNA-binding property for the extracts of TCMs. Seven compounds were found to bind to calf thymus DNA (ct-DNA) from the TCMs of Coptis chinensis Franch (Coptis), but only three ones from Phellodendron amurense Rupr. (Phellodendron) and none from Sophoraflavescens Ait. (Sophora) to bind to ct-DNA. respectively. Three of them were identified as berberine, palmatine and jatrorrhizine and their association constants (K) to ct-DNA were determined by microdialysis/HPLC. Competitive binding behaviors of them to ct-DNA were also investigated. © 2005 Elsevier B.V. All rights reserved.

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Dissertação de Mestrado apresentada à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Engenharia e Gestão Ambiental.

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http://www.archive.org/details/conquestofcontin00burluoft

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Changes in cognition with aging have been claimed to be due in large part to a decline in frontal lobe function. However, at our present state of knowledge, the emphasis on the frontal lobes to the exclusion of the rest of the frontal-striatal circuits of which they are a part is unwarranted. To argue this point, I consider another anatomical candidate within these circuits, the caudate. Evidence is presented that the caudate decreases in size with age as much as the frontal lobes and that damage to either the frontal lobes or the caudate is accompanied by declines in inhibitory processes, executive control, and cognitive speed similar to those seen in normal aging. Separating the unique contributions of the frontal lobes and the caudate to these circuits is difficult but should be the focus of future studies of the biological basis of cognitive aging.

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The passenger response time distributions adopted by the International Maritime Organisation (IMO)in their assessment of the assembly time for passanger ships involves two key assumptions. The first is that the response time distribution assumes the form of a uniform random distribution and the second concerns the actual response times. These two assumptions are core to the validity of the IMO analysis but are not based on real data, being the recommendations of an IMO committee. In this paper, response time data collected from assembly trials conducted at sea on a real passanger vessel using actual passangers are presented and discussed. Unlike the IMO specified response time distributions, the data collected from these trials displays a log-normal distribution, similar to that found in land based environments. Based on this data, response time distributions for use in the IMO assesmbly for the day and night scenarios are suggested