The sub-cellular localization of Sulfolobus DNA replication

Analyses of the DNA replication-associated proteins of hyperthermophilic archaea have yielded considerable insight into the structure and biochemical function of these evolutionarily conserved factors. However, little is known about the regulation and progression of DNA replication in the context of archaeal cells. In the current work, we describe the generation of strains of Sulfolobus solfataricus and Sulfolobus acidocaldarius that allow the incorporation of nucleoside analogues during DNA replication. We employ this technology, in conjunction with immunolocalization analyses of replisomes, to investigate the sub-cellular localization of nascent DNA and replisomes. Our data reveal a peripheral localization of replisomes in the cell. Furthermore, while the two replication forks emerging from any one of the three replication origins in the Sulfolobus chromosome remain in close proximity, the three origin loci are separated.     

长白山北坡静水水体中水甲虫分布与环境关系的典范对应分析

应用典范对应分析（CCA）对长白山北坡静水水体12个样点中28种水甲虫与环境关系的研究表明,长白山5种环境因子中水底腐殖化程度和海拔对水甲虫的分布起主要作用,与排序轴的相关系灵敏分别高达0.8371和0.7206,而水温和植被密度也有较大的影响,在环境因子的影响下不同生境中水甲虫分布的种群不同,深刻斜凹龙虱,端钩切眼龙虱,布朗沟牙甲,沼梭科水甲虫等主要分布在深水区,与水温没有关系。而异毛龙虱和舟型牙甲等与海拔和水泡子的腐殖化程度呈正相关。     

A new system for understanding the biodiversity in different nature reserves:capacity,connectivity and quality of biodiversity

In this paper,we propose a new system for understanding the biodiversity in different conservation areas.It includes three aspects:the capacity,the connectivity and the quality.The capacity refers to the numbers of biodiversity,including absolute and relative richness of the vegetation types Nv and Dv = (Nv-1)/lnA,species numbers S and richness of species dGI = (S- 1)/lnA,and germ plasm resources within a nature reserve,and also the potential biological living space offered by the natural resource.It comprises the total biological resources in a nature reserve.The connectivity refers to the flux of biodiversity,including similarity and connected status of the vegetation types SILi = 2z/(x + y) and species numbers SIc = 2z/(x + y) among different nature reserves.The quality refers to the stability of biodiversity,including relative species richness index RSLi = d/dmax,relative vegetation richness index RVLi =Dv/Dmaxv,fastness to invasion species fLi = 1-Si/St,weighted values,representativeness and vulnerability of special vegetations,special species,CITES species and rare species as the protected targets.     

On the origin of Metazoan adhesion receptors: cloning of integrin alpha subunit from the sponge Geodia cydonium

Integrins are prominent receptors known from vertebrates and the higher phyla of invertebrates. Until now, no evidence has been provided for the existence of integrins in the lowest Metazoa, the sponges (Porifera). We have isolated and characterized a cDNA clone encoding the alpha subunit of integrin from the marine sponge Geodia cydonium (GCINTEG). The open reading frame encodes a polypeptide of 1,086 residues (118 kDa). The intracellular domain features the sequence Tyr- Phe-x-Gly-Phe-Phe-x-Arg, which is different in one residue from the characteristic consensus pattern for integrin alpha subunits. We conclude that sponges, the oldest multicellular animal phylum, already utilize the structural elements which are required for a tuned and controlled interaction among cells, and between cells and the extracellular matrix.      

流感病毒的检测和分型技术研究进展

近年来,病毒性流感的不断流行和暴发已引起世界范围的广泛关注。为了更好地对流感病毒进行检测和分型,我们对目前流感病毒常用的血清学检测和分型方法、免疫荧光法、PCR方法、多重RT-PCR法、实时RT-PCR法、依赖核酸序列的扩增法、环介导等温扩增法、焦磷酸测序法、基因芯片技术分别进行了描述,并阐述了其优缺点。     

Localization of artesunate and its derivatives in the pregnant rat and fetus following oral administration and relationship to developmental toxicity

BACKGROUND: The antimalarial drug artesunate affects erythroid cells leading to developmental toxicity and adult reticulocytopenia. We report on a kinetic study in rats and the tissue distribution of radioactivity following oral administration of [³H]‐artesunate to pregnant rats using quantitative whole‐body autoradiography (QWBA). METHODS: Rats were dosed orally with chlorproguanil/dapsone/artesunate (including 11.8 mg/kg artesunate) and plasma concentrations of artesunate and the active metabolite dihydroartemisinin (DHA) were determined. In the QWBA study, 6 rats received 13 mg/kg [³H]‐artesunate on day 18 of gestation. Groups of 2 rats were euthanized at 1, 6, and 24 hours after dosing, rapidly frozen, and sectioned in a cryostat. Sagittal sections were freeze‐dried and placed in contact with imaging plates. Tissue concentrations of radioactivity were quantified. RESULTS: Systemic exposure to DHA was up to 22‐fold higher than the parent compound and was higher in non‐pregnant females than males. In the QWBA study, high concentrations of radioactivity were seen in maternal tissues involved in absorption and excretion, the bone marrow and spleen. Fetal blood and liver levels were 3.8‐ to 8.8‐fold higher than maternal blood levels at all timepoints. CONCLUSIONS: Excluding tissues involved in absorption and excretion, the highest concentrations of radioactivity were observed in tissues involved in hemoglobin synthesis and/or destruction in both the mother and the fetus and likely account for the maternal reticulocytopenia and embryotoxicity. Radioactivity concentrations in the fetal blood were 2.1‐ to 2.8‐fold higher than maternal bone marrow at all timepoints and this difference could contribute to the lower dose threshold for embryotoxicity. Birth Defects Res (Part B) 89:364–375, 2010. © 2010 Wiley‐Liss, Inc.     

A rapid technique to predict malting quality in barley prior to harvest

Samples of grain from three spring barley cultivars of differing malting quality were collected at regular intervals during four weeks prior to harvest. The samples were dried, then assessed for relative grain hardness using the "Milling Energy" test. Ranking order of the cultivars for this character, which relates strongly to malting quality, was unaltered throughout. In a further experiment, it was demonstrated that selection for milling energy could be successfully practised on oven-dried grain collected six weeks after ear emergence.