食物过敏原研究进展

食物过敏反应是世界各地普遍存在的一个严重问题。本文综述了目前有关食物过敏原研究所取得的进展。包括食物过敏反应流行病学数据,食物过敏原,新过敏原的引物及其监控,通过消除内源基因根除过敏性,移去过敏性抗原基等。     

微环DNA研究进展

质粒载体在基因治疗中占据重要地位.传统质粒DNA在真核生物中可能会引起严重的炎症反应,未甲基化的CpG序列可能抑制基因的表达,最好的解决办法是在生产质粒载体过程中将细菌调控序列整体消除.微环DNA是一种新颖的小环超螺旋表达框,它是传统质粒在大肠杆菌体内通过位点特异性重组得到的.微环DNA缺乏抗性标记基因、复制原点等细菌...     

微生态制剂研究进展

微生态制剂无副作用、无残留、不产生抗性,是理想的抗生素替代品,有着广泛的应用前景。本文综述了国内外近几年微生态制剂的研究现状和开发情况,分析了微生态制剂研究热点及存在的问题,探讨了微生态制剂的发展前景。     

微 RNA 研究进展

近年来,相继发现一些具有调控功能的非编码微RNA,长度约22nt,与基因,细胞周期乃至个体发育过程密切相关,可能对基因功能研究,人类疾病防治及生物进化探索有重要意义。     

鱼类微孢子虫的研究进展

微孢子虫(Microspora)是一类古老的细胞内专性寄生微生物,寄主范围涉及从原生动物到哺乳动物(包括人)的广泛宿主,是许多具有经济价值的昆虫、甲壳类、鱼类、啮齿类、灵长类等动物的病原体。自1857年Nageli首次发现家蚕微粒子病病原生物Nosema bombycis后,人们对其进行了大量研究,特别是近年来,免疫缺陷患者体内微孢子虫的发现,更加引起了生物学界和医学界的广泛关注。其主要生物学特征概括如下:营细胞内专性寄生;具单细胞孢子,孢子内含1-2个核,或简或繁的挤出器,不含线粒体,原始的高尔基 体,似原核生物的核糖体。       

过氧化氢与口腔菌斑微生态学研究进展

1　产生 H2 O2 菌斑微生物192 3年 ,Mclead和 Gorden首先报道肺炎链球菌能产生H2 O2 ,后来学者们又相继发现 β溶血性链球菌和乳杆菌也能产生 H2 O2 [1 ]。尽管口腔菌斑细菌种类多 ,数量大 ,但目前发现能产生 H2 O2 的微生物主要局限于 α-溶血性链球菌。最后一项研究利用超细胞生物化学的方法在龈上菌斑和牙周病变部位的龈下菌斑中观察到一些产生 H2 O2 细菌 ,发现H2 O2 主要存在于细菌的胞膜和胞质中 [2 ]。由于培养条件 ,外源性糖的种类及浓度和采用检测方法不同 ,有关口腔能产生H2 O2 细菌种类的报道存在差异 ,但就产生 H2 O2 …     

南海北部海域春季浮游细菌和病毒空间分布及其影响因素

应用流式细胞检测技术测定了2014年春季南海北部海域浮游细菌和病毒丰度,研究了其水平和垂直分布特征并对其与环境因子的相关性进行了分析。结果表明,调查海区浮游细菌和病毒丰度分别介于1.28×10~4—9.96×10~5个/m L和4.69×10~5—5.39×10~7个/m L之间,二者丰度随水深的增加基本呈现逐渐下降的趋势,而水平分布趋势不明显。浮游细菌和病毒丰度与温度、p H和溶解氧显著正相关,与水深、盐度、活性磷酸盐、硅酸盐、硝酸盐和总氮则呈显著负相关关系(P0.01),说明该海域细菌和病毒数量受到上述环境因子的共同调控。分析浮游细菌和病毒的相互关系发现,VBR(Virus to bacteria ratio)平均32.23,最小值位于S11站位25m层,最大值则位于S7站位75m层,分别为4.80和264.63,VBR值小于100的站位占到调查站位总数的95.6%。VBR值除与细菌呈显著负相关关系外(P0.01),与其它环境因子相关性不明显(P0.05),说明该海区细菌是病毒的主要寄主,病毒可能主要是以噬菌体的状态存在。     

土壤微食物网结构与生态功能

土壤微食物网是碎屑食物网中与土壤生态过程密切相关的一部分,通过取食资源基质直接或间接地参与养分循环过程,影响陆地生态系统功能.本文从土壤微食物网的组成、结构和生态功能等方面综述了近年来土壤微食物网的研究进展.通过对土壤微食物网的能量通道及营养级联效应的介绍,阐述了土壤微食物网在碳(C)、氮(N)转化、凋落物分解和植物生长等方面的重要作用.针对目前的研究现状,提出未来土壤生态学研究应与高通量测序及稳定同位素技术相结合;通过构建模型进一步加强对土壤食物网结构和功能的研究,从而深入揭示地下生态过程及其对地上植物生长的反馈作用机理.     

西藏南部放射虫微体古生物研究进展

西藏南部的雅鲁藏布蛇绿岩带以及该带之南的沉积地层带（特提期沉积区,北喜马拉雅亚区）中广泛发育着大量含放射虫地层,放射虫研究在确定该区蛇绿岩的形成时代,解释造山带复杂的地层层序以及揭示印度板块与欧亚板块在古近纪碰撞老祖宗前的古海洋盆地的演化历史等方面发挥了重要作用。根据已发表的文献以及我们正在进行中的初步成果显示,藏南地区的含放射虫地层的时代分布之中三叠世（安尼期）至晚白垩（土仑期）。这些地层的岩性包括硅质岩,硅质泥岩,凝灰质细碎屑岩和泥晶灰岩等,尽管藏南的放射虫研究已取得一些成果,但系统的放射虫研究与地层研究仍然有待于进一步深入开展。     

乳酸菌的微生态学研究进展

乳酸菌是人和动物正常微生物群或区系(normal microbiota)的组成部分。乳酸菌的生态与正常微生物群的生态是密切相联的,是局部与整体的关系。     

Governance of Ice-Covered Areas: Rule Construction in the Arctic Ocean

This article recounts the negotiations and emergence of Article 234 concerning ice-covered areas in the UN Convention on the Law of the Sea. As Arctic shipping increases, more vessels and flag states may be subject to the provisions of Article 234, which permit coastal states to both prescribe and enforce special measures to protect the marine environment in ice-covered areas. The history of the Article 234, disclosed partially through declassified U.S. government documents, provides context for implementation of the provision by Arctic coastal states and flag states.     

Bacterial diversity in surface sediments from the Pacific Arctic Ocean

In order to assess bacterial diversity within four surface sediment samples (0–5 cm) collected from the Pacific Arctic Ocean, 16S ribosomal DNA clone library analysis was performed. Near full length 16S rDNA sequences were obtained for 463 clones from four libraries and 13 distinct major lineages of Bacteria were identified (α, β, γ, δ and ε-Proteobacteria, Acidobacteria, Bacteroidetes, Chloroflexi, Actinobacteria, Firmicutes, Planctomycetes, Spirochetes, and Verrucomicrobia). α, γ, and δ-Proteobacteria, Acidobacteria, Bacteroidetes, Actinobacteria were common phylogenetic groups from all the sediments. The γ-Proteobacteria were the dominant bacterial lineage, representing near or over 50% of the clones. Over 35% of γ-Proteobacteria clones of four clone library were closely related to cultured bacterial isolates with similarity values ranging from 94 to 100%. The community composition was different among sampling sites, which potentially was related to geochemical differences.     

Ocean currents shape the microbiome of Arctic marine sediments

Prokaryote communities were investigated on the seasonally stratified Alaska Beaufort Shelf (ABS). Water and sediment directly underlying water with origin in the Arctic, Pacific or Atlantic oceans were analyzed by pyrosequencing and length heterogeneity-PCR in conjunction with physicochemical and geographic distance data to determine what features structure ABS microbiomes. Distinct bacterial communities were evident in all water masses. Alphaproteobacteria explained similarity in Arctic surface water and Pacific derived water. Deltaproteobacteria were abundant in Atlantic origin water and drove similarity among samples. Most archaeal sequences in water were related to unclassified marine Euryarchaeota. Sediment communities influenced by Pacific and Atlantic water were distinct from each other and pelagic communities. Firmicutes and Chloroflexi were abundant in sediment, although their distribution varied in Atlantic and Pacific influenced sites. Thermoprotei dominated archaea in Pacific influenced sediments and Methanomicrobia dominated in methane-containing Atlantic influenced sediments. Length heterogeneity-PCR data from this study were analyzed with data from methane-containing sediments in other regions. Pacific influenced ABS sediments clustered with Pacific sites from New Zealand and Chilean coastal margins. Atlantic influenced ABS sediments formed another distinct cluster. Density and salinity were significant structuring features on pelagic communities. Porosity co-varied with benthic community structure across sites and methane did not. This study indicates that the origin of water overlying sediments shapes benthic communities locally and globally and that hydrography exerts greater influence on microbial community structure than the availability of methane.     

Footprints of climate change in the Arctic marine ecosystem

In this article, we review evidence of how climate change has already resulted in clearly discernable changes in marine Arctic ecosystems. After defining the term ‘footprint’ and evaluating the availability of reliable baseline information we review the published literature to synthesize the footprints of climate change impacts in marine Arctic ecosystems reported as of mid‐2009. We found a total of 51 reports of documented changes in Arctic marine biota in response to climate change. Among the responses evaluated were range shifts and changes in abundance, growth/condition, behaviour/phenology and community/regime shifts. Most reports concerned marine mammals, particularly polar bears, and fish. The number of well‐documented changes in planktonic and benthic systems was surprisingly low. Evident losses of endemic species in the Arctic Ocean, and in ice algae production and associated community remained difficult to evaluate due to the lack of quantitative reports of its abundance and distribution. Very few footprints of climate change were reported in the literature from regions such as the wide Siberian shelf and the central Arctic Ocean due to the limited research effort made in these ecosystems. Despite the alarming nature of warming and its strong potential effects in the Arctic Ocean the research effort evaluating the impacts of climate change in this region is rather limited.     

Cumaceans as Indicators of Atlantic Waters over the Continental Slope of the Arctic Ocean

The material on cumacean fauna of the continental slope of the Arctic Ocean (more than 80 samples) was collected during expeditions with the ships Persei in 1925, 1928, and 1936; Sadko in 1936; and Polarstern in 1990, 1993, and 1995. Examination of the samples (150–900 m depth) revealed 19 species of Cumacea in this region. Three Arcto-Atlantic bathyal species (Hemilamprops uniplicatus, Diastylis echinata, Campylaspis globosa) are markers of the places over the continental slope where Atlantic intermediate waters penetrate into the Arctic Ocean and reach to the bottom. These species are widespread in the North Atlantic (100 to 2882 m depth); on the continental slope of the Arctic Ocean, they occur in a narrow depth range (200 to 900 m) in areas where positive temperatures from 0.09 to 1.78°C and high salinity of 34.75 to 34.87 prevail. The locations of these species is delineated on maps as an interrupted belt extending from northeastern Greenland to the East Siberian Sea and further north up to 79°30 N and 148° E, which corresponds to the route of penetration of Atlantic intermediate waters into the Arctic Ocean.     

Debates over the Role of the Arctic Council

This article examines the role(s) that the member governments want the Arctic Council to have in Arctic Ocean affairs. The article identifies and examines three determining debates over the role and future of the Arctic Council: The first preceded the Arctic Council's creation in 1996, the second occurred during and as a result of the Ilulissat meeting in 2008, and the third followed the political shift in the United States in 2009.     

微生物生物膜研究的新进展

微生物在生长过程中为适应生存环境而形成了生物膜,Dr.Costerton JW在生物膜方面的研究为我们开拓了微生物学的新领域。微生物生物膜是由微生物群体及其包被的细胞外多聚物和基质网组成,它们彼此黏附或者黏附到组织或物体的表面。微生物生物膜与微生物的耐药性形成、基因的转移以及引起机体的持续性感染等都密切相关。目前对生物膜的研究重点已经深入到微生物相互间的信号传递、致病基因的转移以及如何干预微生物生物膜的形成等方面。此外,在治理污水和环境保护工程、生物材料工程和食品工业等方面,微生物生物膜技术已经得到了应用。     

Complete genome sequence of Thalassolituus oleivorans R6-15, an obligate hydrocarbonoclastic marine bacterium from the Arctic Ocean

Strain R6-15 belongs to the genus Thalassolituus, in the family Oceanospirillaceae of Gammaproteobacteria. Representatives of this genus are known to be the obligate hydrocarbonoclastic marine bacteria. Thalassolituus oleivorans R6-15 is of special interest due to its dominance in the crude oil-degrading consortia enriched from the surface seawater of the Arctic Ocean. Here we describe the complete genome sequence and annotation of this strain, together with its phenotypic characteristics. The genome with size of 3,764,053 bp comprises one chromosome without any plasmids, and contains 3,372 protein-coding and 61 RNA genes, including 12 rRNA genes.     

Isolation and phylogenetic analysis of cultivable manganese bacteria in sediments from the Arctic Ocean

Isolation, molecular identification and phylogenetic analysis were carried out to investigate the biodiversity of manganese bacteria in sediments which were collected from the Arctic Ocean during the 2^nd Chinese Arctic Scientific Expedition. 21 and 19 species of cultivable strains were isolated from sediments at Stations P11 and S11, respectively, according to their distinct morphological character on the screening plate of manganese medium. Molecular identification and phylogenetic analysis showed that the cultivable manganese bacteria from Station P11 were basically composed of γ-Proteobacteria (γ subgroup of the Proteobacteria branch of the domain Bacteria) and Actinobacteria, which accounted for 86% and 14%, respectively. The isolates of γ-Proteobacteria mainly included Psychrobacter, Shewanella, Acinetobacter and Marinobacter, of which Psychrobacter was the major genus, which accounted for 67% of the γ-Proteobacteria. The cultivable manganese bacteria from Station S11 included α-Proteobacteria, γ-Proteobacteria and Flavobacteria of Bacteroides. The γ-Proteobacteria mainly included Shewanella, Marinomonas and Alteromonas. The majority of α-Proteobacteria was Sphingomonas. The phylogenetic analysis indicated that bacteria from sediments at Stations P11 and S11 had different cultivable manganese microbial communities. All tested strains had higher resistance to Mn²⁺, of which Marinomonas sp. S11-S-4 had the highest resistant ability.     

Isolation and phylogenetic analysis of cultivable manganese bacteria in sediments from the Arctic Ocean

Isolation, molecular identification and phylogenetic analysis were carried out to investigate the biodiversity of manganese bacteria in sediments which were collected from the Arctic Ocean during the 2nd Chinese Arctic Scientific Expedition. 21 and 19 species of cultivable strains were isolated from sediments at Stations P11 and S11, respectively, according to their distinct morphological character on the screening plate of manganese medium. Molecular identification and phylogenetic analysis showed that the cultivable manganese bacteria from Station P11 were basically composed of γ-Proteobacteria (γ subgroup of the Proteobacteria branch of the domain Bacteria) and Actinobacteria, which accounted for 86% and 14%, respectively. The isolates of γ-Proteobacteria mainly included Psychrobacter, Shewanella, Acinetobacter and Marinobacter, of which Psychrobacter was the major genus, which accounted for 67% of the γ-Proteobacteria. The cultivable manganese bacteria from Station S11 included α-Proteobacteria, γ-Proteobacteria and Flavobacteria of Bacteroides. The γ-Proteobacteria mainly included Shewanella, Marinomonas and Alteromonas. The majority of α-Proteobacteria was Sphingomonas. The phylogenetic analysis indicated that bacteria from sediments at Stations P11 and S11 had different cultivable manganese microbial communities. All tested strains had higher resistance to Mn2+, of which Marinomonas sp. S11-S-4 had the highest resistant ability.