1α,25-双羟维生素D3作用于靶细胞的机制

1α,2 5-双羟维生素 D3 [1 α,2 5(OH) 2 D3 ]作用于靶细胞后产生 2种不同的信号传导系统 :基因效应和非基因效应。前者是指 1α,2 5(OH) 2 D3 与维生素 D核受体 (n VDR)结合 ,n VDR再与视黄酸 X受体 (RXR)发生异二聚化反应 ,在转录因子 (TF)的作用下 ,促使靶基因转录。后者是指 1 α,2 5(OH) 2 D3 与维生素 D膜受体 (m VDR)结合 ,随之引发一系列信号传导 ,促使细胞膜上的 Ca2 -通道迅速打开。探讨 1α,2 5(OH) 2 D3 的作用机制有利于开发治疗维生素 D内分泌系统疾病的新药。本文就目前有关 1 α,2 5(OH) 2 D3 作用于靶细胞的机制的研究成果进行综述。     

中国对虾体内钴镍含量及其变化规律的研究

钻(Co)和镍(Ni)是动物生长发育必需的微量元素[1],它们与动物体内许多酶的活性与功能具有密切的联系[2].缺Co将影响维生素B₁₂的合成速度和丙酸的代谢过程;缺Ni则使淀粉酶与肝脏脱氢酶的活性降低,从而影响氨基酸的代谢[3].关于中国对虾(Penaeus chinensis)在生长过程中Co,Ni的含量与变化规律及其相互关系,国内外尚未见报道.笔者采用原子吸收分光光度计测定不同体长的天然对虾和养殖对虾体内Co,Ni的含量,并通过多元分析方法揭示中国对虾在不同生长阶段Co和Ni的变化规律以及它们之间、它们与其体长之间的相互关系.     

3-(3′-羟基)丁基苯酞氨基酸酯衍生物的设计与合成

3-(3′-羟基)丁基苯酞是丁苯酞在体内的代谢产物,具有多种药理作用,可以作为一种新的活性成分应用于药物开发中。本文以甘氨酸、甲硫氨酸和亮氨酸为起始原料,经过Boc保护,再与3-(3′-羟基)丁基苯酞进行缩合,脱保护3步反应合成了3-(3′-羟基)丁基苯酞的氨基酸酯。以期提高水溶性和改善药代动力学性质,获得3-(3′-羟基)丁基苯酞的前药。     

补肾活血中药联合维生素D对PCOS不孕患者内分泌及抗氧化作用的影响

目的：观察补肾活血中药联合维生素D对多囊卵巢综合征（PCOS）不孕患者内分泌及抗氧化的作用。方法：选取PCOS不孕患者90 例作为研究对象,以随机数字表法分为中西医结合组、中药组、西药组,每组各30 例。中西医结合组给予补肾活血中药联合维生素D辅助干预治疗,中药组仅予补肾活血中药治疗,西药组给予克罗米芬治疗。将3个月经周期定为1个疗程。治疗1～2个疗程后比较3组患者排卵率、妊娠率、性激素［包括雌二醇（E₂）、促卵泡生成素（FSH）、促黄体生成素（LH）、雄激素（T）］和25-羟维生素D（25OHD）、丙二醛（MDA）、超氧化物歧化酶（SOD）水平。结果：中西医结合组及中药组均可有效提高E₂2及25OHD水平,降低T及MDA水平,对FSH、LH有调节性作用,可进一步提高妊娠率,且在调节内分泌方面中西医结合组较中药组、西药组疗效更佳（P＜0.05）。结论：补肾活血中药联合维生素D辅助治疗PCOS不孕患者,可以明显改善内分泌代谢及氧化应激状态,提高临床妊娠率。     

脊椎动物中维生素C合成能力的研究进展

维生素C(VC)广泛参与动物体内诸如羟化反应和氧化还原反应等多种生化反应。大多数脊椎动物具备VC合成能力,其中L-古洛糖酸-1,4-内酯氧化酶(GLO)是其生物合成的关键酶。GLO在体内合成位置随脊椎动物进化地位从低到高总体上呈由肾脏向肝脏转移,最后消失的趋势。GLO基因突变是导致某些脊椎动物无法合成Vc的原因。此外,GLO的活性还受物种、性别、发育阶段、季节变化以及食物中抗氧化剂的影响。然而,导致部分脊椎动物缺乏Vc合成能力的原因及其在进化中的重要意义仍需深入研究。     

反复呼吸道感染患儿维生素A、D、K水平与中医证型相关性分析

目的：分析反复呼吸道感染（RRTI）患儿维生素A、D、K水平特点,并探讨其与中医证型的相关性,为RRTI的防治提供新的思路。方法：选取228例3～7岁RRTI患儿为研究对象,收集其临床资料并进行中医辨证分型,并纳入74 例同年龄段的正常儿童作为对照组。比较2组儿童的维生素A、D、K水平;并采用Logistic回归分析探讨RRTI组儿童维生素A、D、K水平与中医证型的关系。结果：RRTI患儿的维生素A、D水平低于正常组儿童（P＜0.01）;维生素A水平与肺脾气虚型RRTI、维生素D水平与脾肾两虚型RRTI、维生素K水平与胃肠积热型RRTI的发病率呈负相关。结论：RRTI患儿的维生素A、D水平偏低;且维生素A、D、K水平与RRTI中的某些中医证型存在相关性。     

维生素C对水产动物的功用及其保护方法

维生素Ｃ（Ｖｃ），又名抗坏血酸（Ｌ ａｓｃｏｒｂｉｃａｃｉｄ），对水产动物的正常生理生化功能具有重要作用。大多数陆生动物在体内能够合成Ｖｃ，但大多数的水产动物体内不能合成Ｖｃ ,它们对Ｖｃ的缺乏都很敏感。另外 ,在Ｖｃ的化学结构中 ,高度活泼的第２位碳原子上的羟基很不稳定 ,容易被空气氧化。在饲料加工过程中 ,约有８０ %～９８ %的Ｖｃ被破坏 ,此外在包装、贮藏、投喂等环节Ｖｃ也易丧失活性。因此 ,稳定型Ｖｃ已成为国内外水产研究的一个热点。１维生素Ｃ的功用Ｖｃ在生物体内一个重要的生物学功能是参与胶原蛋白的合成。…     

维生素D可降低糖尿病风险

英国学者的最近一项研究证明：在婴儿期补充维生素D可使日后罹患Ⅰ型糖尿病的风险降低29％。这个结论与之前的研究结果相吻合：阳光可促进体内维生素D的合成，因此在那些阳光充足的国家人们患Ⅰ型糖尿病的几率较低；冬季日照较少，Ⅰ型糖尿病的病例就会突然增多。研究者发现，刚被诊断为Ⅰ型糖尿病的患者血液中的维生素D低于正常水平。维生素D缺乏不仅会引起佝偻病和Ⅰ型糖尿病，还可能导致风湿性关节炎和多发性硬化症等自身免疫性疾病。     

嗜碱盐单胞菌X3中异化型硝酸盐还原酶编码基因簇的功能验证及蛋白结构预测

细菌的氮代谢推动环境的氮循环,硝酸盐还原反应是氮代谢途径中重要步骤之一。本文运用酶活测定、qRTPCR和生物信息学软件分析的方法,对嗜碱盐单胞菌(Halomonas alkaliphila)X3中编码细菌异化型硝酸盐还原酶(Dissimilatory nitrate reductase,Nar)不同亚基的基因簇narGYJV进行了功能验证、蛋白结构预测和系统发育分析。研究表明,X3菌株中存在narGYJV基因簇并具有表达活性,测得Nar的酶活为每克蛋白21.415U;预测到的narGYJV编码蛋白功能区域中1～1246氨基酸属于NarG超家族,编码Nar的α亚基;1261～1752氨基酸属于DMSOR-beta-like超家族,编码Nar的β亚基;2061～2279氨基酸编码γ亚基,1802～2018氨基酸编码δ亚基;Nar的二级结构中无规卷曲占37.59%,α螺旋占34.43%,延伸链占18.33%;NarG、NarY和NarV的3D结构与PDB中大肠杆菌(Escherichia coli)的1Q16 3D结构最接近,覆盖率96%～100%。系统发育树显示,菌株X3中NarG与同属菌的遗传距离较近,在不同菌属间虽然功能相似,其同源性较低;NarY与大肠杆菌中的氨基酸序列的同源关系较近,说明异化型硝酸盐还原酶Nar中不同亚基的系统发育地位不同。研究结果表明,Halomonas alkaliphila X3菌株中存在编码Nar的基因簇narGYJV,编码蛋白具有独特的3D结构,不同亚基的系统发育地位不同。研究结果为进一步研究该菌的氮代谢通路选择和调控机制提供了依据。     

海产贝类体内类胡萝卜素的研究进展

类胡萝卜素是一类脂溶性的大分子量的有机化合物,在染色、医药、食品等行业中具有很高的应用价值.类胡萝卜素也广泛地存在于海产贝类体内.本文详细综述了国内外海产贝类体内类胡萝卜素的来源、种类和含量、功能及吸收代谢方面的研究状况,为今后的研究提供参考.     

不同剂型和剂量的维生素C对幼刺参生长的影响

在水温11.0～14.0℃条件下,将平均体质量2.29 g的幼刺参(Apostichopus japonicus)随机放入39个容积50 L塑料水槽中,投喂以玉米蛋白为蛋白源,分别添加0、500、1 000、2 000和4 000 mg/kg V_C-2-三聚磷酸酯(L-ascorby1-2-polyphosphate, LAPP)、V_C-棕榈酸酯(L-ascorby1 palmitate, LAP)和V_C -磷酸酯镁(L-ascorby1-2-monophosphate-magnesium, APM)的13种饲料.90 d的饲养情况表明,摄食添加V_C饲料的刺参的生长、蛋白质效率均显著高于摄食未添加V_C的幼参(P＜0.05).摄食添加LAPP饲料幼参的特殊生长率最高(0.21%/d),添加LAP(0.17%/d)的次之,添加APM(0.15%/d)的最低,分别比对照组(0.12%/d)高75.00%、41.67%和25.00%.摄食添加LAPP饲料幼参的平均蛋白质效率最高(12.57%),摄食添加LAP饲料的(7.76%)次之,摄食添加APM(6.86%)的最低,分别比对照组(5.52%)高127.72%、40.58%和24.28%.在3种剂型V_C组中,饲料系数由低到高依次为:LAPP＜LAP＜APM.饲料中LAPP、APM和LAP的添加量为2 000～2 500 mg/kg、1 000～1 500 mg/kg和2 000～3 125 mg/kg时,幼刺参对饲料蛋白的表观消化率最高,生长最快,饲料系数最低.     

Biochemical and physiological disturbances in fish inhabiting coastal waters polluted with bleached kraft mill effluents

An extensive trial to examine physiological and biochemical changes in perch (Perca fluviatilis) inhabiting coastal waters polluted by bleached kraft mill effluents has been carried out. The results from this investigation show profound effects of bleached kraft mill effluents on several fundamental biochemical and physiological functions on four different sampling occasions. Typical symptoms in perch from the polluted areas were reduced gonad growth, enlarged liver, and very strong induction of certain cytochrome P-450-dependent activities. Elevated content of ascorbic acid in liver tissue and strongly affected carbohydrate metabolism show that the effluent causes metabolic disorders. Marked effects on the white blood cell pattern indicate a suppressed immune defence. Alterations in the red blood cell status and the ion balance suggest an impaired gill function. This extensive symptom picture is strengthened by the relatively good agreement with the effects previously observed in fish exposed to bleached kraft mill effluents (BKME) in the laboratory.^1–3     

棘皮动物神经肽的研究进展

神经肽是神经系统最大、最多样化的一类信息分子,可调节动物的各种生理过程和行为。相较于脊椎动物和原口无脊椎动物,棘皮动物神经肽的研究起步较晚,而棘皮动物关键的分类地位和独特的生物学特征为其神经肽信号系统功能的研究提供了特殊背景。本文从神经肽分子的自身特性出发,对棘皮动物神经肽的作用方式、鉴定方法、功能调节及受体发掘等相关研究成果进行了综述,并对其未来的研究进行了展望。以期进一步解析神经肽在棘皮动物特殊生理行为调控中的作用机制,为棘皮动物中经济物种的高效绿色增养殖提供理论支撑。     

Cytochrome P450 gene diversity and function in marine animals: past, present, and future

The biotransformation of xenobiotics by microsomal cytochromes P450 is known to be pivotal in the effects of some compounds, and thought to be so for many. A knowledge of CYP gene diversity and CYP function and regulation in aquatic species is pursued, expecting that it will disclose mechanisms, allow predictions regarding species differences in susceptibility, and provide markers for exposure to xenobiotics. As well, it is hoped that such knowledge will provide clues to CYP endogenous functions, and to the origin and functional significance of CYP gene diversity. The knowledge of CYP in marine and other aquatic species is expanding rapidly. The diversity of CYP genes in non-mammalian vertebrates may approximate that in mammals. At present, cloning studies have identified members of gene families 1 to 4 have been cloned from one or more fish species. Where known, the gene structures of fish CYP genes are like those of mammalian homologues. Only one CYP1A gene has been identified in most fish species examined. Fish CYP1As, including multiple forms from recent divergence in some genera, have structural and catalytic properties more like CYP1A1, but also have properties that are 1A2-like, consistent with fish CYP1As representing the CYP ancestral to both CYP1A1 and CYP1A2. A number of genes cloned from several species have been classified in the 3A subfamily. Fish CYP3As catalyze steroid 6β-hydroxylase, and have other properties consistent with mammalian 3As. Recently identified CYP4 genes classify to novel subfamilies but apparently are homologues of mammalian CYP4 genes, and may act on similar substrates. The greatest diversity of fish CYP genes is in family 2; there are now six fish CYP2 subfamilies known. Four of these are novel subfamilies, although cladistic analysis suggests distinct relationships to mammalian CYP2 subfamilies. Heterologous expression and characterization of some of these CYP have identified similar functions among genes in different subfamilies. For example, fish CYP2Ns and CYP2Ps are related to mammalian CYP2Js, and CYP2P3 and CYP2J2 have strikingly similar functions as fatty acid epoxygenases and hydroxylases, with nearly identical regio- and enantioselectivity for metabolism of arachidonic acid. In addition to sequence and catalytic similarities, there also are indications that CYP regulation, tissue and cellular localization are similar between fish and mammals. Yet even in cases where orthology is strongly suggested, e.g. CYP1A, there appear to be taxonomic differences in active site structure suggesting potential differences in involvement of CYP1A in toxicity. In contrast to fish, CYP diversity and functions in aquatic invertebrates are poorly known. Investigators have identified novel gene families and subfamilies in crustaceans (CYP2L; CYP45), molluscs (CYP30, CYP10) and sponges (CYP38). CYP4C genes occur in crustaceans, molluscs and echinoderms, and a new subfamily (CYP4Y) in molluscs. The future? There is no doubt that new CYP will continue to be discovered in non-mammalian vertebrates; some (e.g. CYP51) can be predicted confidently. And, there is no doubt that the numbers known in invertebrates will expand greatly. In insects and C. elegans the numbers are very high, and even slime molds have 18 CYP genes. It is virtually certain that CYP genes with unique functions will be discovered. While the knowledge of CYP genes is increasing, knowledge of CYP function and regulation lag well behind. Technical approaches to speed the aquisition of such knowledge are available. The information will be essential to discern the role that CYP play in the disposition and toxicity of xenobiotics, during development as well as in adults. Yet, when such data are in hand, we may have to face the paucity of information on the diversity, function and regulation other enzymes, notably the glutathione S-transferases, glucuronyl transferases and sulfotransferases, in aquatic species. Discerning orthologous relationships among CYP genes, as well as those for phase II enzymes, could highlight gene lineages associated with conserved and endogenous functions. Understanding CYP endogenous functions, as well as their metabolism of xenobiotics, may reveal fully the ways that chemicals cause toxicity. [Support: Sea Grant NA46RG0470-R/P61, EPA R-829890, NIH ES07381].     

无鱼粉日粮条件下黄颡鱼生长性能和肝胰脏转录组差异表达的研究

本研究以黄颡鱼(Pelteobagrus fulvidraco)为试验对象,设计两种饲料:鱼粉组和无鱼粉组,在池塘网箱中投喂70 d,研究其生长性能和肝胰脏转录组表达的差异。同鱼粉组相比,无鱼粉组黄颡鱼特定生长率下降了30.25%(P0.05),饲料系数显著增加了83.94%(P0.05),全鱼脂肪含量显著下降(P0.05),血清甘油三酯含量显著下降(P0.05),血清转氨酶活力显著增加(P0.05)。肝胰脏转录组结果显示,总计有12 020个基因差异表达,其中差异表达上调的基因有5 020个、差异表达下调的基因有7 000个。同鱼粉组相比,无鱼粉组分别有1 013个基因表达显著上调、2749基因表达显著下调(P0.05)。将组间具有差异表达的基因进行GO Term、KEGG pathway分类,结果显示:无鱼粉组的肝胰脏细胞组成、细胞生物过程、细胞分子功能等绝大多数基因差异表达下调,提示肝胰脏的细胞组织结构和功能受到很大的影响;KEGG通路富集到15个显著差异代谢通路。本研究结果表明,日粮中鱼粉可能含有某些生理活性物质,这些物质以神经分泌、激素调控、代谢信号通路等为作用靶点,通过对这些代谢信号通路的调节,对鱼的整体生理代谢强度、细胞结构与功能、生理健康状态等产生明显积极促进影响。缺乏这些物质则会造成黄颡鱼生长性能下降、部分器官组织细胞(肝细胞、神经轴突)受到损伤、鱼体抗应激能力和免疫防御能力下降。     

贻贝对麻痹性贝类毒素的蓄积代谢研究进展

麻痹性贝类毒素（paralytic shellfish toxins,PSTs）能够导致贝类、鱼类等海洋生物染毒或死亡,危害海洋生态安全及人类健康。其中,贻贝具有强蓄积性特点,在国外可作为PSTs的指示性生物。近年来,我国因食用贻贝造成多起PSTs中毒事件成为安全关注重点,因此急需弄清其风险形成机理。本文通过综述我国近海贻贝等贝类中PSTs的风险程度、贻贝对不同产毒藻来源的PSTs的蓄积作用,分析环境因子对于蓄积代谢的影响,深入挖掘贻贝蓄积代谢特异性。进而聚焦贻贝代谢阶段的表达调控过程、影响因素、转化作用及方式等。未来应侧重于摸清我国目标区域贻贝等海洋贝类中PSTs基础风险规律和变化过程,并据此建立区域性PSTs风险防控技术,提高我国贻贝中PSTs风险的主动防控能力,对于保障消费者健康和海洋生态安全具有积极意义。     

饲料维生素C对美国红鱼(Sciaenops ocellatus)组织NO含量、NOS活力和nNOS基因表达的影响

本试验旨在研究饲料维生素C对美国红鱼(Sciaenops ocellatus)组织中的NO含量、NOS活力和NOS基因表达的影响。采用单因子试验设计,将360尾平均体重为(147.28±7.69)g的美国红鱼随机分为6个处理,每个处理设3个重复,每个重复20尾,分别饲喂6种不同维生素C水平(0、49.3、98.9、197.5、396.4和1989.8mg/kg)的等氮等能饲料,进行为期8周的生长试验。结果表明:头肾、肝、肠、胸腺NO含量随着饲料维生素C含量增加有显著增加;脾中各组NO含量无显著性差异;脑中NO含量C0组与其它各组相比有显著性差异。头肾、肝、胸腺NOS活力随着饲料维生素C含量增加有显著增加;脾和肠中各组NOS活力无显著性差异;脑中NOS活力C396.4组与其它各组相比有显著性差异。脑中各组nNOS基因mRNA的表达含量无显著性差异;在饲料维生素C含量达到1989.8mg/kg时,其它各组织内的nNOS基因mRNA的表达量最高。综上所述,饲料中添加适当维生素C对美国红鱼组织中的NO含量、NOS活力和nNOS基因mRNA的表达有显著影响。     

Isolation and characterisation of pristane metabolites formed in vivo by rainbow trout

Pristane (2,6,10,14 -tetramethylpentadecane) occurs ubiquitously in the marine environment. This hydrocarbon may be of biogenic or petrogenic origin.¹ Recently it has been shown that residual amounts of this branched alkane increased in marine organisms after an oil spill.^2,3 The lack of data on the fate of pristane in fish, added with the fact that this compound was considered by some authors as a non-metabolisable substance in vertebrates, including man,⁴ led us to investigate the capability of fish to metabolise pristane. In this study, urinary and fecal excretion, tissue distribution and metabolism of ³H-pristane were analysed in Salmo gairdneri R. after a single intragastric dose. In addition to unchanged hydrocarbon, various labelled compounds have been isolated and identified in liver, bile, faeces, urine and surrounding water, demonstrating that pristane was first oxidised to alcohols (pristanol and pristane-diol) and to acid (pristanic acid). The elimination of these compounds occurred in the form of conjugated products (primarily glucuronides) as well as free metabolites.     

Latitudinal variation in the aerial/aquatic ratio of oxygen consumption of a supratidal high rocky‐shore crab

The colonisation of the terrestrial environment by crustaceans is more apparent in tropical latitudes because of the high diversity of semi‐terrestrial and terrestrial crabs. However, in temperate regions there are also great numbers of crustaceans that inhabit ecological niches at the water–air interface. Grapsidae crabs (Decopoda) are especially important in studies of water‐to‐land transition as the family contains species occupying the intertidal and adjacent regions. A way to evaluate the ability of intertidal invertebrates to breathe air is to measure the aerial/aquatic oxygen consumption ratio. The objective of this study was to test the effect of thermal variation on the aquatic and aerial metabolism. We selected as study model the decopoda crab Cyclograpsus cinereus Dana and utilised five populations of the species spread over 2000 km along the Chilean coast. To determine the compensation capacity in respiration with respect to latitude, we evaluated metabolic rate at the same temperature in a common garden design in the laboratory, to examine the extent to which variation in crab physiology is environmentally determined. Whereas in our study, m_b (body mass) varied significantly with latitude, the difference in mass‐independent metabolism both in air and water persisted, indicating that observed differences in MR (Metabolic Rate) were not an effect of differences in body size. We demonstrated that C. cinereus is able to breath oxygen from air and water as expected for an amphibious crab. Almost all the studied populations of C. cinereus show a aerial/aquatic metabolism ratio near 1. The pattern found indicates an increase in metabolic rate, both aerial and aquatic, in low latitudes and therefore does not support the latitudinal compensation hypothesis for temperate habitats. Finally, these kinds of studies are required to make the necessary link between ecological physiology and macroecology and to help develop a global understanding of organismal function in marine systems.     

长江航道水下地形三维可视化研究

三维地形可视化技术是现代地理信息技术的研究热点,广泛应用于地理信息的各个领域。通过长江中游太平口水道水下地形的三维建模,阐述了三维地形可视化技术在长江航道测绘领域的应用与发展,通过实例介绍了航道三维立体可视化图的制作过程。