自然曝气生物滤床去除二级污水处理厂尾水中酚类内分泌干扰物的应用

采用自然曝气生物滤床工艺对二级污水处理厂尾水进行深度处理。结果表明该工艺可在净化过程中创造良好的好氧环境,对尾水中悬浮颗粒物(SS)、化学需要氧量(COD)和氨氮(NH₄⁺)的去除效率分别可达76%、45%和77%。尾水中可检出不同程度的酚类内分泌干扰物,其中双酚A(BPA)、壬基酚(4-NP)、辛基酚(4-t-OP)、三氯生(TCS)和雌酮(E₁)的浓度在1～1639ng/L之间,未检出雌二醇(E₂)和炔雌醇(EE₂)。该工艺可显著削减上述有机微污染物的含量,去除效率分别可达49%、63%、78%、80%和46%。4-NP、4-t-OP和TCS的去除效率随水力负荷(HLR)减小而升高,E₁的去除效率不随HLR变化而变化,BPA的去除效率随HLR减小而下降,主要因为强疏水性有机物可在吸附竞争中降低疏水性较弱的有机物在系统中的吸附能力。     

林睡鼠幼鼠的活动规律和行为初步观察

本文通过红外线照相的方法,对发育期的林睡鼠幼鼠进行室内活动规律及行为观察,为充分了解林睡鼠越冬前的能量储备形式提供饲养参考。将鼠密度监测仪固定在饲养笼具上方,24h连续拍照,采集和分析6-9月年龄在10周内的幼鼠各种活动数据。结果显示：幼鼠一天中超过70%的时间都在窝内度过,大部分时间都蜷缩成一团少有动作;在窝外活动时间多在玩耍,如攀爬笼架。用于进食和饮水的时间不超过全天的2%。林睡鼠幼鼠主要活动时间在21:00-07:00,活动高峰在21:00-03:00之间。幼鼠出生3周后开始出窝活动,哺乳期30d后开始采食,5周后幼鼠有交配玩耍行为。随着日龄的增长,活动高峰从23：00提前到21：00,活动时间也逐渐延长,但9周龄后活动时间逐渐缩短,幼鼠的饮水进食时间与其活动的时间长短较为一致。10周体重可达成年体重的70%。研究表明,林睡鼠在夏秋季节基本是昼伏夜出动物。光照是影响其在外活动的重要因素之一。幼鼠6周后所需的饲料和水量大于成年林睡鼠,在此期间要注意饲料和水的补充。     

福建三都澳游泳动物种类组成及群落结构稳定性

利用2012-2013年三都澳渔业资源的定置张网调查资料, 应用物种多样性指数、数量生物量比较曲线(ABC曲线)及鱼类分类多样性指数等方法分析三都澳游泳动物种类组成特征和群落结构的稳定性。调查中共出现游泳动物195种, 隶属于17目64科125属, 其中鱼类143种, 甲壳类47种, 头足类5种。大黄鱼(Larimichthys crocea)在三都澳4个航次的调查中都是最主要的优势种类, 其他优势种类还包括叫姑鱼(Johnius belengerii)、白姑鱼(Argyrosomus argentatus)、虾虎鱼类和一些甲壳类。大黄鱼多为养殖群体, 其他优势种类的共同特征是个体小, 繁殖周期短, 生物量季节或年际间波动剧烈。物种多样性分析表明, 三都澳游泳动物群落平均Shannon-Wiener多样性指数为2.61, 9、10月高, 1、5月低。ABC曲线分析表明, 4次调查中群落结构存在明显的变化, 繁殖群体的补充、个体生长、捕捞、伏季休渔等是影响群落结构稳定性的因素。本次研究表明, 大黄鱼生物量的比例与Shannon-Wiener多样性指数呈极显著负相关(P < 0.01, R = -0.890), 与种类数呈显著负相关(P < 0.05, R = -0.563)。结合近年来的调查数据, 统计得到三都澳的现存鱼类约224种, 其平均分类差异指数(△⁺)为59.5, 分类差异变异指数(∧⁺)为260.8。相对于中国沿海其他海域, 三都澳鱼类群落分类学范围较小, 且群落间的分类地位关系极不均匀, 群落抗干扰的能力较差。     

Land eco-security evaluation in the Shule River Basin during 2005–2014 in Gansu Province,China

The Shule River Basin is an ecologically fragile area in arid zone. To understand the state of land eco-security, the Environment-Economic-Society model was applied to build a land eco-security evaluation index system in the Shule River Basin. An entropy-weighted and matter-element model was built for eco-security evaluation from 2005 to 2014. Principal component analysis was used to quantitatively study the limiting factors of land ecological security. The result showed: the direction of development of the state of land eco-security in the Shule River Basin from 2005 to 2014 was characterized by “unsafe (No₄) → safe (No₁),” and presented an upward trend. The land eco-security status during 2005–2007 was in the “Unsafe” state and the state changed to “Critical Safe” in 2008–2009, “Safer” in 2010–2011, but “Safe” in 2012–2014. The key factors that affected land eco-security in the Shule River Basin were Per Capita Arable Land, Forest Cover Rate, Per Capita Water Resources, Water Production Modulus, the Tertiary Industry Output Value, and GDP Ratio and Water Consumption. Among them, Forest Cover Rate and Water Production Modulus had the greatest impact, with principal component loads of up to 0.973 and 0.968, respectively. The result of this study is expected to serve as reference and support for the conservation and management of Shule River Basin to ensure sustainable development.     

Development of recombinant <Emphasis Type="Italic">Yarrowia lipolytica</Emphasis> producing virus-like particles of a fish nervous necrosis virus

Nervous necrosis virus (NNV) causes viral encephalopathy and retinopathy, a devastating disease of many species of cultured marine fish worldwide. In this study, we used the dimorphic non-pathogenic yeast Yarrowia lipolytica as a host to express the capsid protein of red-spotted grouper nervous necrosis virus (RGNNV-CP) and evaluated its potential as a platform for vaccine production. An initial attempt was made to express the codon-optimized synthetic genes encoding intact and N-terminal truncated forms of RGNNV-CP under the strong constitutive TEF1 promoter using autonomously replicating sequence (ARS)-based vectors. The full-length recombinant capsid proteins expressed in Y. lipolytica were detected not only as monomers and but also as trimers, which is a basic unit for formation of NNV virus-like particles (VLPs). Oral immunization of mice with whole recombinant Y. lipolytica harboring the ARS-based plasmids was shown to efficiently induce the formation of IgG against RGNNV-CP. To increase the number of integrated copies of the RGNNV-CP expression cassette, a set of 26S ribosomal DNA-based multiple integrative vectors was constructed in combination with a series of defective Ylura3 with truncated promoters as selection markers, resulting in integrants harboring up to eight copies of the RGNNV-CP cassette. Sucrose gradient centrifugation and transmission electron microscopy of this high-copy integrant were carried out to confirm the expression of RGNNV-CPs as VLPs. This is the first report on efficient expression of viral capsid proteins as VLPs in Y. lipolytica, demonstrating high potential for the Y. lipolytica expression system as a platform for recombinant vaccine production based on VLPs.     

沉默马铃薯Sgt1-3基因减少块茎糖苷生物碱积累

马铃薯茄啶 糖基转移酶（solanidine glycosyltransferase,Sgt）家族成员Sgt1、Sgt2和Sgt3参与糖苷生物碱（glycoalkaloids,GAs）合成。已有研究证明,抑制该家族任一成员表达可影响马铃薯块茎中糖苷生物碱合成;然而,对Sgt家族成员的单基因实施调控很难有效降低块茎中总糖苷生物碱的积累。为降低马铃薯块茎中总糖苷生物碱的含量,本研究拟采用RNAi技术,对糖苷生物碱合成代谢途径末端酶基因家族成员Sgt1 3在转录水平进行共调控。为实现这一目的,构建了块茎特异性启动子Patatin驱动的,以Sgt1、Sgt2和Sgt3基因为靶向的RNAi表达载体pCEI-PFR,采用农杆菌介导法转化马铃薯茎段,获得10株可沉默Sgt1、Sgt2和Sgt3基因表达的Patatin RNAi融合基因的转基因植株。实时定量PCR（RT-qPCR）结果显示,Sgts基因的相对表达量分别降低了大约32%～60%（Sgt1）、29%～55%（Sgt2）和25%～66%（Sgt3）,而草甘膦抗性基因--5-烯醇式丙酮酸-3-磷酸莽草酸合酶（5-enolpyruvylshikimate-3-phosphate synthase, EPSPS）的表达量则增加了约48%～135%。高效液相色谱法（HPLC）证明,尽管转基因株系的绿色组织中糖苷生物碱含量与野生型无显著差异,但块茎中糖苷生物碱分别比野生型降低了46%～59%（庄薯3号）和42%～62%（Favorita）。上述结果提示,复合沉默茄啶 糖基转移酶家族基因可降低马铃薯块茎中糖苷生物碱的积累。此外,该结果可能对研究马铃薯不同组织间糖苷生物碱的分布和积累,以及马铃薯种质资源的创新开发具有一定启示。     

Reconsidering connectivity in the sub‐Antarctic

Extreme and remote environments provide useful settings to test ideas about the ecological and evolutionary drivers of biological diversity. In the sub‐Antarctic, isolation by geographic, geological and glaciological processes has long been thought to underpin patterns in the region's terrestrial and marine diversity. Molecular studies using increasingly high‐resolution data are, however, challenging this perspective, demonstrating that many taxa disperse among distant sub‐Antarctic landmasses. Here, we reconsider connectivity in the sub‐Antarctic region, identifying which taxa are relatively isolated, which are well connected, and the scales across which this connectivity occurs in both terrestrial and marine systems. Although many organisms show evidence of occasional long‐distance, trans‐oceanic dispersal, these events are often insufficient to maintain gene flow across the region. Species that do show evidence of connectivity across large distances include both active dispersers and more sedentary species. Overall, connectivity patterns in the sub‐Antarctic at intra‐ and inter‐island scales are highly complex, influenced by life‐history traits and local dynamics such as relative dispersal capacity and propagule pressure, natal philopatry, feeding associations, the extent of human exploitation, past climate cycles, contemporary climate, and physical barriers to movement. An increasing use of molecular data – particularly genomic data sets that can reveal fine‐scale patterns – and more effective international collaboration and communication that facilitates integration of data from across the sub‐Antarctic, are providing fresh insights into the processes driving patterns of diversity in the region. These insights offer a platform for assessing the ways in which changing dispersal mechanisms, such as through increasing human activity and changes to wind and ocean circulation, may alter sub‐Antarctic biodiversity patterns in the future.     

Molecular engineering and plant expression of an immunoglobulin heavy chain scaffold for delivery of a dengue vaccine candidate

In order to enhance vaccine uptake by the immune cells in vivo, molecular engineering approach was employed to construct a polymeric immunoglobulin G scaffold (PIGS) that incorporates multiple copies of an antigen and targets the Fc gamma receptors on antigen‐presenting cells. These self‐adjuvanting immunogens were tested in the context of dengue infection, for which there is currently no globally licensed vaccine yet. Thus, the consensus domain III sequence (cEDIII) of dengue glycoprotein E was incorporated into PIGS and expressed in both tobacco plants and Chinese Ovary Hamster cells. Purified mouse and human cEDIII‐PIGS were fractionated by HPLC into low and high molecular weight forms, corresponding to monomers, dimers and polymers. cEDIII‐PIGS were shown to retain important Fc receptor functions associated with immunoglobulins, including binding to C1q component of the complement and the low affinity Fcγ receptor II, as well as to macrophage cells in vitro. These molecules were shown to be immunogenic in mice, with or without an adjuvant, inducing a high level IgG antibody response which showed a neutralizing potential against the dengue virus serotype 2. The cEDIII‐PIGS also induced a significant cellular immune response, IFN‐γ production and polyfunctional T cells in both the CD4⁺ and CD8⁺ compartments. This proof‐of‐principle study shows that the potent antibody Fc‐mediated cellular functions can be harnessed to improve vaccine design, underscoring the potential of this technology to induce and modulate a broad‐ranging immune response.     

The critical role played by endotoxin-induced liver autophagy in the maintenance of lipid metabolism during sepsis

Macroautophagy/autophagy is a central mechanism by which cells maintain integrity and homeostasis, and endotoxin-induced autophagy plays important roles in innate immunity. Although TLR4 stimulation mediated by lipopolysaccharide (LPS) also upregulates autophagy in hepatocytes and liver, its physiological role remains elusive. The objective of this study was to determine the role of LPS-induced autophagy in the regulation of liver lipid metabolism. LPS treatment (5 mg/kg) increased autophagy, as detected by LC3 conversion and transmission electron microscopy (TEM) analysis in C57BL6 mouse livers. AC2F hepatocytes also showed increased autophagic flux after LPS treatment (1 μg/ml). To investigate the role of LPS-induced autophagy further, liver lipid metabolism changes in LPS-treated mice and fasted controls were compared. Interestingly, LPS-treated mice showed less lipid accumulation in liver than fasted mice despite increased fatty acid uptake and lipid synthesis-associated genes. In vitro analysis using AC2F hepatocytes demonstrated LPS-induced autophagy influenced the degradation of lipid droplets. Inhibition of LPS-induced autophagy using bafilomycin A₁ or Atg7 knockdown significantly increased lipid accumulation in AC2F hepatocytes. In addition, pretreatment with chloroquine aggravated LPS-induced lipid accumulation and inflammation in C57BL6 mouse livers. The physiological importance of autophagy was verified in LPS-treated young and aged rats. Autophagic response was diminished in LPS-treated aged rats and lipid metabolism was impaired during sepsis, indicating autophagy response is important for regulating lipid metabolism after endotoxin challenge. Our findings demonstrate endotoxin-induced autophagy is important for the regulation of lipid metabolism, and suggest that autophagy helps maintain lipid metabolism homeostasis during sepsis.